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

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I used to have Fitbit versa both 1 and 2 they were amazing with accuracy of sleep. Then I switched to Garmin Vivoactive 4 and everything else is fine but the sleep tracking is way off. You could be awake and just spend some time in bed, Fitbit would take that as awake but Garmin would count that as still sleeping. Also garmin does not seem to catch naps whereas Fitbit does. It is a shame Fitbit's future is a little unclear because like you I am also looking for my next watch but can't seem to find a good alternative.
I still have to first generation versa. It still runs great to this day 6 years later. It’s a shame what has happened to Fitbit over the years
I bought a Sense a few years but the screen cracked so I bought Versa (2maybe?) and the battery completely broke and now I'm back to my original Sense! Cracked but still works well! I've been wanting a new fitness tracker, and while I have been using Fitbit for many years, I've been so disappointed but I just don't know what else I would be happy with.
Charge 6 might still be on sale for 100. Never really used the Smartphone functions on my versa, liking the charge so far Charge does have healthconnect, which is a standard for apps and other devices to share health stuff. I don't know if that works with apple.
Damn. I had no idea they that bad. I used a Fitbit verse for years and it would last like a week even with rides and such.
My seventh Fitbit died last week (from Luxe to Versa to Charge 5 and 6, this was my second in-warranty replacement), white line on the screen to no screen at all within 24 hours. So with some Target credit I decided to go with a Garmin Instinct for $200. The GPS is much, much more accurate (even when not paired with my phone), the app tracks a lot more information than the Fitbit app did and takes up a third of the space on my phone. I miss the constant step updates; the Garmin just updates every minute. That's about the only drawback.
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.

Ranked #1
Oura - Oura Ring Series

Ranked #1
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