Garmin
Forerunner 255 Series
Long battery; but wrist HR tracking is inconsistent.

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Fenix 6X PRO. Was a new open box item in John Lewis and marked down to £276 about 3 years ago. I’d been looking at an instinct and then saw this and jumped on it. Can’t fault it.
I tried using both and ended up swapping fully to Apple. You mention maps - having used the Fenix range for maps on hiking, camping and climbing - including solo where it really matters - I find Apple smashes the Fenix. The maps are more usable, quicker to respond, clearer and much easier to use. I hardly ever used my Fenix for mapping because it was a poor experience, compared to onboard maps on my AWU2. I had a Fenix 6x pro, a chest strap, foot pod, tempe, scales, edge 830, speed sensor and cadence sensor. Yet it’s all been sold when I started to use Apple, because the Garmin stuff felt dated, clunky and unreliable. The maps were more of a “wow, maps on your wrist” kind of feature. They were too slow and uneasy to make them usable however. And the lack of Garmin working happily with anything other than the dated ANT hardware made Garmin very isolated whether at the gym, using scales or blood pressure devices at home or using connected training kit at the gym - Apple works with it all. And even Garmin pay, if you’re on the UK, is useless. Very few banks support it. Whereas Apple Pay is accepted by all. Pairing my Apple Watch up with Footpath and Bevel (new update is amazing) has blown Garmin out the water. It’s a much better fitness and outdoor watch than some other brand users give it credit for. Which is probably why it’s the best selling fitness watch brand in the world. Garmin isn’t a bad brand, but it’s failed to innovate and progress over the last 5 or 6 years. Their hardware is decent, their software and apps are poor. The user interface is dated and they still fail to produce a decent fitness watch with modern smart features. At present Garmin caters for those who want a fitness watch and aren’t bothered about smart features. Apple caters for those who want a fitness watch with smart features. So it’s good that there’s a choice for both types of people. Just like I don’t buy a tractor, because I don’t need one. But my SUV would be a nightmare for a farmer who didn’t care about all the features and extras my SUV has. Go with the brand of your choice and whatever suits your needs. We’re all different.
The charger on the Garmin was one of those nightmare features. Had many times where I woke to a dead or low powered Fenix because someone had sneezed several houses down the road and my connection to the charger had moved slightly, stopping my Fenix from charging. Not sure who designed this charger, but it was the worse design ever. Made worse by the fact that the charging point on the back of the Fenix slowly worsened over time with sweat from workouts. I had to buy a rubber stopper to cover it. Very annoying design flaw.
I own a Fenix 6X Pro. I like the cheapness, battery life and no touchscreen. If I had to buy another watch today I would get an Enduro 2 most likely. Run 30 - 40 miles per week.
I’m actually going the other way: Fenix 6X Pro Solar to Apple Watch Ultra 3. I’ve always disliked the Garmin connect app interface, it’s just gross to navigate and use. There’s been a ton of bugs I’ve experienced with my 6X both on the watch itself and with the connection to the Garmin Connect app. In general the software experience with Garmin feels clunky and buggy. Most people don’t care I suppose since it (usually) works for just tracking workouts. The new Fenix line is way overpriced in my opinion, where the AWU is looking much more appealing. For the same price as a Fenix 8, I’m rocking an Oura Ring 4 for sleep tracking and AW Ultra 3 for everything else. It is far nicer to track your sleep with an unobtrusive ring rather than a bulky and uncomfortable sports watch (whether Garmin or Apple Watch). The AW also has satellite and cellular, which is even more expensive with the Fenix 8 Pro. It’s a goodbye to Garmin for me. I’ll keep my Fenix 6X if I ever need to do a super long gps recording, still works.
I have a Garmin Fenix 8 AMOLED 51mm, I had about 40% left after my 100 miler a couple months ago. I was previously on the Garmin Fenix 6x pro but noticed battery life wasn’t last quite as long as it used to so I upgraded
Fenix 6X Pro because my previous Garmin watches were Forerunners that didn't last very long before they began having bluetooth issues. I was really angry to deal with that through two watches after only a year and a half on each watch, so I thought I'd buy the flagship to give Garmin one last chance, and it's been an absolute TANK for 3.5 years now.
Garmin
Forerunner 255 Series
Long battery; but wrist HR tracking is inconsistent.

Garmin
Forerunner 955 Series
Best value, clear MIP screen; limited smartwatch features.

Garmin
Fenix 7 Series
Durable, multi-week battery, flashlight; high price, buggy software.
Garmin
Instinct 2 Series
Rugged, solar multi-week battery; bulky, small screen readability issues.

Garmin
Enduro 3
Multi-week solar battery, lightweight; but bulky form factor.

Ranked #1
Oura - Oura Ring Series

Ranked #1
Apple - Ultra Series

Ranked #1
Garmin - Enduro 3

Ranked #1
Garmin - Fenix 7 Series

Ranked #1
Garmin - Forerunner 255 Series

Ranked #1
Oura - Oura Ring Series