Garmin Fenix 6 vs Garmin Fenix 7 vs Garmin Descent Mk 2

Fenix 3 Setup
Fenix 3

You know I can’t resist a good gadget, and my Garmin Fenix 3 watch has to be one of the best. I use it every day, not only as a timepiece but also many of its other features too. It has so many features that there probably are some that I don’t use (I don’t play golf for a start so don’t use that part of it). There are however many things on it that I use every day or even several times a day and many many others that I use on occasion.

As a quadrathlete and triathlete I use many of the sport related features as that’s what it is all about really. It’s essentially a GPS tracking device complete with a whole host of other sensors.It also connects to many other devices such as heart rate monitors, cadence sensors, smart trainers and power meters too so can track every aspect of your training and racing. It also connects to my phone and acts to a certain degree as a smart watch as well. In fact, it’s unbelievable what it can do and just how much I use it.

I use it whilst swimming, both in the pool and open water. I use it whilst cycling, either on my road bike, mountain bike, gravel bike or indoors on the trainer. I use it running, wherever I happen to be running and I use it whilst kayaking, surf-skiing or paddle-boarding. I also use it whilst windsurfing and surfing. It even counts the waves that I catch and tells me how long they were! I’ll have it connected to my heart rate strap for most of the above and my power meter when I’m using one. I also have a footpad on my running shoes that it can connect to if I want. Although that is a little redundant as the accelerometer in my heart rate strap is used for all sorts of running dynamics these days.

Whilst training I might use it to help me stick to a certain pace or follow a particular set of training intervals. Sometimes I’ll use the virtual partner to race myself, and others I’ll use it to help me train at a certain power level, pace or heart rate zone.

If I’m out walking in the hills or trekking up a mountain I use it, not only to track where I’ve been but also as a navigational tool. I do of course have (and know how to use) a map and compass as well. However, unless the terrain gets particularly tricky or I find myself a little unsure I tend to just rely on my watch these days. For many of the activities I do I often plot a route online before leaving and then use my watch to help me follow it so that I don’t get lost.

It tracks my sleep, it tracks my steps each day, it tracks my heart rate variability and it tracks my training load and corresponding stress and recovery levels. It can tell me what my lactate threshold is based on run pace and effort and my cycling and run VO2 Max as well. I use it to tell me what the tide times and heights are and to tell me when sunset and sunrise is. It has a barometric altimeter so it tells me what elevation I’m at, and it uses the altimeter to give me storm warnings as well. It also has a thermometer built into it, but that isn’t great as it’s too close to my body heat so doesn’t really give any meaningful readings.

It even tells me where my car is if I’ve parked it in a large super-market car park and forgot where I left it!

With so much going on in such a cool device you wouldn’t think there was much that they could add to it. You would be wrong.

New Features upon New Features

Fenix 6
Fenix 6

My Fenix 3 is now quite old now – well, only in technology terms anyway. I first got it in early 2015 and I was one of the first to get one in the UK. Since then it has served me well. I have replaced it with a like-for-like model from Garmin at a much reduced price after one of the buttons started sticking. Now, after years of constant use it is feeling a little long in the tooth. Garmin are now onto the Fenix 6 and the Fenix 7 is likely to be released later in 2021. Over the years they have iterated the watch a number of times and each version has of course had new features.

The Fenix 3 HR added a wrist based optical HR monitor.

The Fenix 5 added loads of things such as a larger screen, more colours on the display, increased battery life, a gyroscope, compatibility with lots of new sensors, FTP estimation, training load functionality, Live Group Tracking, Strava Live Segments, additional sport modes and plenty of other things too.

The Fenix 5X added topographic mapping and a number of related navigational and mapping features. Yes, it now comes loaded with full topographic maps of Europe.

The Fenix 5 Plus added full colour maps, Trendline Popularity Routing, Music playback capabilities along with headphone connectivity so that you can listen to tunes whilst training, contactless NFC payments with Garmin Pay, a new GPS chipset, Climb Pro, a Pulse Oximeter, more improvements to battery life and a full dataset of 40,000 worldwide golf courses.

The Fenix 6 adds even more functionality with options of larger sizes and large screens, solar charging in some of the top end models, map themes, PacePro, power management features to improve battery life even further and power modes that you can select and customise based on your needs, ski resort maps, wrist based swimming heart rate, more data fields per screen, Widget Glances, better battery life (now up to 80 days in battery saver mode), Respiration rate (when used with a chest strap), Training Load Focus, more training metrics, ‘Body Battery’ functionality, heat and altitude acclimatisation, crash and incident detection, safety/tracking assistance and a few other things.

How can a single little watch do quite so much?

Time for an Upgrade

As you may have guessed I’m thinking of an upgrade! The beauty of waiting 6 years or so and not buying the new version each time it comes out is that if I upgrade to the Garmin Fenix 6 from the Garmin 3, I’ll get all of those new features listed above so there will be loads of new things to play with. Again, I’m sure I won’t use all of them but there are quite a few things there that I’d like.

Which Model Garmin Fenix?

There are quite a few different models of the Fenix 6 available.

Fenix 6 Models
Fenix 6 Models

Based on the current Fenix 6 models I think my choice would be the Garmin Fenix 6X Sapphire. The 6X has a larger screen than the 6S or 6 (and of course my Fenix 3) but is about the same size overall size as my Fenix 3. If anything it is slightly slimmer I think. The sapphire screen does add to the cost over the standard 6X Pro but the sapphire screen on my Fenix 3 has been amazing. Despite the abuse I throw at it, there isn’t a blemish on it. It has amazed me on a number of occasions and was well worth the extra cost as far as I’m concerned. Speaking of cost, these things aren’t cheap. In fact, they are expensive and in some cases very expensive but I use it so much that I do think I get my moneys worth from them.

Wait for the Fenix 7?

Of course, the Garmin Fenix 7 will be out soon and that will add even more into the mix. No one knows what yet, but it’s likely that the solar powered features might make it to all models of the range. ECG monitoring might be added and there might even be a bit of a design change. No doubt there will be some other things too along with incremental improvements across the board. I’ve yet to decide if I should hang on for the 7 to be released. Waiting would mean that I could decide if I wanted the new features and then not feel left out if I do. If the new features in the 7 aren’t for me then waiting would probably mean the 6X would come down in price anyway. Not waiting would of course mean that I could get it now!

Umm, Hang on, what’s the Fenix Descent Mk2 all about?

Descent Mk2

There is one other thing to take into consideration. Morgan wants to get into Scuba Diving and I’m hoping to re-start with him. Now, the Fenix 6 (or the 7) aren’t Dive Watches they are multi-sport watches. In fact, people don’t really use ‘dive watches’ these days as they use dive computers instead. Dive Computers track you diving stats, advise you on decompression times, help with ascent rates, help you plan dives, calculate no fly times and all sorts of other things. They are invaluable to a modern diver and of course are very expensive too. If we do get into diving then it is likely to be a gadget that we’ll need.

However, Garmin make a watch called the Garmin Descent Mk2. This is essentially a Garmin Fenix 6X Sapphire with a built in Dive Computer!!!! How cool is that! It does everything that the Fenix 6 does but also has all of the dive features of a dive computer (half of what I don’t even know what they are!). At £1200 I’m very unlikely to get, but if I were properly into diving again it would probably make sense as it would be one watch to rule them all rather than having a multi-sport watch and a dive computer which would work out more expensive. There’s even a £1400 version that connects wirelessly to an additional sensor on your regulator so as to tell you how much air you have left as well!

Here are the dive features alone!

Dive Features of Descent Mk2

The Descent Mk2 is certainly an impressive piece of kit and would be my definite choice were I into diving again but it’s more likely that I either wait for the Fenix 7 or get the Fenix 6X Sapphire.


For me I think the highlights of the upgrade will be

  • Better, more colourful, larger screen as I do have trouble reading some of the smaller text on mine these days – the perils of ageing!
  • Topographic Maps
  • 24/7 Heart Rate Monitoring
  • Swimming Heart Rate
  • Music
  • Strava Live Segments
  • Pulse Oximetry

The things such as improved training and recovery metrics, body battery and training effects will be nice too.

Altitude and heat acclimatisation will be interesting and would have been nice for my recent trips up Mount Toubkal and Kilimanjaro. They are likely to be interesting rather than useful though as there wasn’t much I would have been able to do differently whatever my watch was telling me about my altitude acclimitisation.

The fact that it has 2,000 ski resorts and 40,000 golf courses pre-loaded into the watch probably won’t be any use to me either. Although I am over 50 now and I do have a Golf Course about 10 metres from the house so you never know. And yes, Borth Golf Course is on the list of courses loaded into the watch – I checked! Not that I know anything about golf or quite what the watch does while you’re golfing but the features sound kind of cool – maybe not cool enough for me to take up golf just yet though!

I’m not going to take the plunge just yet, but it really is an amazing piece of kit and it won’t be long before one is gracing my wrist I’m sure.

8 Responses

  1. Avatar forComment Author Mum x says:

    I thought no way am I going to read all that ..but I did !
    I must admit you do at least use most of the features unlike most people
    My watch is used to tell the time and nothing else,
    Who knows you may take up golf ..,I do remember you having a couple of rounds at Ashton Court about forty years ago X

  2. Avatar forComment Author Simon says:

    Its the exact situation you describe that i am in now.
    Haha so funny to read. And hei such a cool article…

    Here is my problem… i was just reading this:

    I practice freediving not scuba diving. My range of outdoorsport is big too. Mostly parkour, workouts climbing cliffjumping, surfing and alot of co2 tolerance training for my freediving.

    Here is the thing. It looks that the mk2 misses many software features of the fenix 6 pro. Now i do not freedive as often as i do the other things. But still once i dive i miss having a gadget that tells me how depths i am. But i also know i would miss all this software options in the mk2 that is supposrted by the fenix 6pro

    How would you proceed? Buy both ??? ?

    • Avatar forComment Author Alan Cole says:

      Interesting… I’m unlikely to buy the descent anyway but I will have to investigate.

      Buying both would be good, but I think if I were to go down that route i’d get the Fenix 6X Sapphire and a dedicated dive computer, not necessarily the Descent MkII


    • Avatar forComment Author Fran says:

      Hola ,perdona por escribir en Español . ( Espero que el traductor automático haga su trabajo solo)
      Yo tengo mi fénix 3 y hago carrera bicicleta nado..
      También buceo y apnea..
      Para la apnea uso mi Mares Exel ( buceo+apnea) .
      Lo cual es fundamental para mi tiempo en superficie recuperación..
      Me estoy pensando compra no oficial que se introduce al fénix usando su barómetro como profundimetro . Lo instalé pero no lo he usado ..

  3. Avatar forComment Author Alan Cole says:

    Well, I’ve bought a Fenix 6X Sapphire. I like it!! 🙂

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Alan Cole

Alan is a Freelance Website Designer, Sports & Exercise Science Lab Technician and full time Dad & husband with far too many hobbies: Triathlete, Swimming, Cycling, Running, MTBing, Surfing, Windsurfing, SUPing, Gardening, Photography.... The list goes on.

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