Garmin
Forerunner 255 Series
Long battery, but wrist HR often inaccurate.

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Yes I love this watch but whilst I did say money is not an option I would not spend that much I think
Marq gen 2.. It is a good looking watch (I got it at a discount at REI with other credits).
They are paid apps, but your TCO is less than a Garmin if you want something that gives you Siri/voice commands etc (by which I mean cost over 3/4 years inc purchase, apps and resale value). Yes to HRV/VO2 etc. And much more. WorkOutDoors is the other app you’ll need if navigating outdoors matters to you. No argument from me - this is less seamless than Garmin’s all in one solution. I also won’t argue that the Ultra doesn’t go far enough to bridging the gap with Garmin in this regard. Battery life is also a major factor. Hardcore adventurists need multi-day battery. 95% of users do not. Upsides with AWU is of course, cell/data, seamless Apple integration, voice commands etc. Your choice is determined by how much Garmin’s inbuilt solution matter to you vs how much you use /will lament Apple functionality. FYI, I’m wearing my beloved Marq2 as I write this. I’m a total Garmin fanboy, but I’m also realistic about the AWU being a perfect solution for most people.
Garmin has to be one of the most stubborn refuse to change companies out there. I mean has anyone looked at their executive team lately. Bunch of clueless old guys that don’t appear to have any athletic ability anymore & never had any fashion sense. We ask for a whoop competitor & we get an index sleep monitor. However don’t worry we’ve released a screenless tracker for your horse. I’ve had a ton of Garmins over the years. Including multiple Marqs. Now because Garmin won’t listen to their customers I’ve moved over to Amazfit & Whoop(have had one for like 7 years) I’d gladly go back to Garmin if they would release what we’ve asked for, a proper screenless Whoop competitor. Garmin wake up already. Of course I’ll be checking out Polar’s offering next week. Hope they nail their band.
it was all about battery life for me. And in that case it's the garmin and not even close. I had a 1st gen Ultra and switched to the Marq with zero regrets.
for battery life, you can't really go wrong with Garmin. really good watches, although they might lack a bit on the actual 'smart' side of functionality in comparison to something like an Apple Watch. for stylish design, I would go for either the Forerunner or Fenix line (forerunners are simpler/sleeker, while Fenix watches look slightly more rugged but still pretty nice). If you really want the most stylish option, I feel obligated to also mention the Marq line, but I would not recommend those to anyone unless the look is a MUST because those are crazy expensive for features comparable to a previous gen Fenix model.
I personally can't provide the difference in 'smart' features as I've never owned a Pixel watch or something similar, my current Garmin fenix 7 pro is the 'smartest' watch I've had. I think the main selling point of those other watches is that they are basically replacements of your phone, with a lot of functionality being possible on there. something like a Garmin (Coros and Amazfit also go this route I believe) doesn't have that but does win significantly when looking at things like battery life or 'outdoor' functionality. Garmin does seem to be moving into the 'smart' side more with products like the Fenix 8 (that one now has microphone/speaker) and the Venu, but they are still behind Apple and Samsung on that front. There are a lot of videos on Youtube comparing Garmin to the Apple Watch products, so I think that might be something to look at if you are unsure which way to go.
Garmin
Forerunner 255 Series
Long battery, but wrist HR often inaccurate.

Garmin
Forerunner 955 Series
Endurance battery, value king, but clunky UI.

Garmin
Fenix 7 Series
Rugged, long battery, maps, but HR and software can struggle.
Garmin
Instinct 2 Series
Extremely durable, multi-week battery, physical buttons, but bulky.

Garmin
Enduro 3
Unrivaled multi-week battery, solar-charged, but bulky.

Ranked #1
Oura - Oura Ring Series

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Apple - Ultra Series

Ranked #1
Garmin - Fenix 7 Series

Ranked #1
Garmin - Fenix 7 Series

Ranked #1
Garmin - Forerunner 255 Series

Ranked #1
Oura - Oura Ring Series