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

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Honestly, I've had a galaxy watch8 for a few months and the sleep tracking has been garbage - with random gaps all over the place. It's already been sent away and repaired twice, and I need to send it away for repairs again because they didn't replace the faulty sensors in the first place. I guess if it all works as it's meant to...it would be pretty darn good watch as the metrics and analysis provided are quite useful (I have a few chronic medical conditions so sleep tracking is of some importance to me). Interestingly, I've never encountered the random gaps in sleep tracking issue with any prior devices I had which just worked properly without the need for mucking around with settings in the random hope that it will track sleep somewhat correctly.
I do too, I found watches were always getting sweaty and trapping the moisture whilst I was asleep, yuuck Unfortunately there's no other good rings aside from Oura. Best watch replacement so far looks to be the Samsung Galaxy watch 8, does the menstrual tracking via temperature + very good sleep tracking, as good as Oura, according to that scientist guy on YouTube
If you like battery life, I can't recommend the Watch 8. I just got it yesterday, and after tracking two 1 to 1 1/2 hour workouts — beginning at 80% charge — it was out of juice already. It also took 20% just while sleeping. It was also in sleep mode.
Probably the same, if not just a little bit worse.
It mostly depends on how you use your watch. If you do a lot of workouts and want to track those, I don't believe that's too great of a pick unless you have some chance of charging it a lot. Everything about the Watch 8 is pretty cool and I like it a lot, but the battery life seems atrocious to me. It's how you use it and nothing else.
It'll do perfectly fine then. After doing some research and testing, I can tell that the AOD takes quite a bit of power as well. Once I turned that off, it was quite fine.
Mind telling me how you use it? E.g. do you have your AOD on? That's especially curious since I also use the 40mm.
Liked the 8 until I saw it in person. Love the squircle case shape. Hate that the screen stayed a circle with the case shape.
Love mine, had it for 3.5 years. Will upgrade to the 4 now. I also wear a Samsung ring, Samsung Galaxy Watch 8, and Whoop band. Oura has been my longest worn device and has provided tremendous insights as it's gotten to know me and my routines/cycles over the years.
Currently using both a Samsung Galaxy Watch 8 as well as a Samsung Fit Band 2. Both work well for basic workouts and sleep tracking. I have been considering switching over to Garmin smartwatches since they would better integrate to my Garmin 1050 cycling computer as well as the Garmin app. I'm planning on getting into triathlons in the future so having it all be one ecosystem would be pretty convenient for tracking purposes. I've also thought of getting a smart ring. I like wearing mechanical watches when I'm not working out and would prefer not to have to wear a second watch/tracker just for steps and heartrate.
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