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

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I have an amazfit GTR2E it gives me a couple of weeks battery charge on normal use, heat rate, sleep fitness, etc. That's the reason I brought it for the battery life. It's a couple of years old now and has never been a problem. I know it's out of date now, but if the new amazfit watches are as good as the older ones, I would definitely go for amazfit again when I'm ready to replace mine.
I'm still rocking an Amazfit GTR2 with Gadgetbridge. I get all functions and notifications, music control and you can even get some cool watchfaces from 3rd party sites. Although I'm a fitness junkie I'm not much into the health functions and/or how accurate they are. I mostly keep an eye on stepcount but that's about it. I don't use my watch or phone to pay, I'm old-school and still use my plastic card or cash. The best thing about Amazfit watches is the humongous battery life. I own this watch since about 5 years and I still get 2 solid weeks of battery life 👍😊
I had the amazfit stratos and it was great, then the GTR2e and it was absolute wank! GPS was the worst I've ever seen! Ended up just sending it back it was so bad! Edit: [side by side comparison with Garmin if you're curious ](https://www.reddit.com/r/amazfit/s/HtaWDR3q0f)
Amazfit gtr2e - impossible to deplete the battery, cheap, good looking except for the strap. I was eyeing Google watch for a while (and still am), but Samsung watch 6 was cheaper.
I had Amazfit gtr-2, than Garmin venu 2s, Garmin venu 3 and now Amazfit T-Rex 3. I'm not serious runner, I just do workouts in the gym, some hiking, cycling, paddle board. Garmin was ok, but I prefer Amazfit for better value/price.
Look for the BiP or the active smart model based on your liking. Before my Garmin, I rocked a gtr2e which I still have as a backup smartwatch
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