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

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Garmin Forerunner 935 was going strong and was about to hit the 5 year point... until I did the stupid thing of freediving with it.
Forerunner 935, had to wear my friends enduro for my one 100 miler though but it just about sees me through 100k
Fenix 8 47mm Sapphire. I've had a range of Garmins (Forerunner range: 35, 235, 935, 945, 955) but the 970 didn't appeal to me (accent colour on side and domed glass) so I got my first Fenix and first AMOLED watch (solar was thicker than my 955 which was already a bit thick under clothing). Love the look of the Fenix a lot more, plus better battery life
My 2019 Garmin Forerunner 935 is still going strong.
Ahhh I miss my forerunner 935 with its 2 week battery life, those were the days, this ultra 2 is not hateful though. Garmin does make a decent outdoor activity watch though.
I like my Garmin Forerunner 935. I liked the Fenix as well. Battery is great. It tracks swimming pretty well in the pool, I just turn it off when I'm kicking only. It does open water too. I use it for running and cycling and it's great - pace, time, laps, elevation, heart rate etc.
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
Enduro 3
Unrivaled multi-week battery, solar-charged, but bulky.

Garmin
Forerunner 965
Lightweight, vibrant AMOLED, maps, but wrist HR and swim issues.

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Oura - Oura Ring Series

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Apple - Ultra Series

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Garmin - Fenix 7 Series

Ranked #1
Garmin - Fenix 7 Series

Ranked #1
Garmin - Forerunner 255 Series

Ranked #1
Oura - Oura Ring Series