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

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Watches arent designed to be upgraded every year - there's very little difference from the model 5 years ago to the latest one. If you're going from FE to Ultra then yeah, but you'll notice a bigger difference going from say a watch 7 FE to a watch 7 ultra than you will going from a watch 5 FE to a watch 7 FE (if it exists, but you get my gist) Samsung used to have a "comparison" page where you could compare one model to another. See if that's still there, and see if there's anything you REALLY care about that justifies the cost. The main difference with watch generations is "how long is it supported" , but again, unlike phones, that rarely means you'll get new features. If your watch works, then keep it. You'll likely be dissapointed with the improvements compared to the cost difference. I went from a Gear Watch 3 classic to a watch4 classic and felt like there was zero difference, then from a watch4 to a watch7 ultra and the only difference I notice is the screen size. Its a watch. I dont spend hours looking at it. I dont run high-load apps on it. Its a watch. If I had made either of those upgrades at retail cost I woukd be gutted and feel ripped off. Headphones , however, can be noticeably different. Depending on your appreciation of music, what you listen to, how you listen to it, etc. If you havent got a tuned-ear, only listen to highly-processed pop or country, and use Spotify- then buds pro are probably also not worth the upgrade. But still more worth it than a minor watch upgrade.
The "no- phone" condition is what made me buy a lte smart watch. I own a samsung galaxy watch 4 classic lte for years and it serves the purpose very well. If you're buying now it sold be galaxy watch 7 lte which is on sale for ~13k in republic day sale. On the apple side i would suggest SE3 lte. FYI my owns a SE2 lte.
I'd say go for the OnePlus Watch 3, it has Garmin-like battery life with all the WearOS goodies. edit: the OHealth app also provides a lot of stats for my runs, but the watch in general is a bit more strict when it scores your sleep or calculates the burned calories, etc. I had a GW4 classic, compared to that the calorie consumption for the same workout is always less by a good 10-20% (not sure which is more accurate)
I still have the watch 4 classic as well. Need a steeper discount as well
Got the 4 Classic from launch.. battery seems pretty shot, worth the upgrade to the classic or ultra?
No issues or complaints here but then again I only compare it to my GW4C and pixel has been more accurate. I don't get super nerdy or care about GPS being a little off like some do. Good news is the ps4 is supposed to have a better gps.
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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Garmin - Fenix 7 Series

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Garmin - Fenix 7 Series

Ranked #1
Garmin - Forerunner 255 Series

Ranked #1
Oura - Oura Ring Series