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

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I am using Galaxy Watch 7 and Amazfit Active 3. Amazfit is closer to my professional medical devices from work. Edit: and topo maps are better than any app on Wear Os
I just upgraded to the galaxy watch 7 (just set it up it minutes ago) 40mm and the Watch 4 classic looks better and the rotating bezel protects the screen. I'm a little scared to break or scratch the glass of the 7. But it's quicker indeed, and lighter but let's see if battery life is better, I don't use the screen always on but was having bad battery life on my aged watch 4, that wad the main reason. I considered the OnePlus Watch 3 for its great battery life but since I own a Samsung s24 ultra decided to buy a used 7 for 81 euros.
If you're worried about battery life, I wouldn't go lte. Drains battery faster. Same thing with your phone on mobile data vs wifi. My gw7 dropped almost 30% battery to youtube music in around 3 hours of playback. That was using my galaxy buds, and having the songs pre-downloaded... on the 44mm Bluetooth model.
Oh yeah without youtube, I took this thing off at 3 am yesterday... at 65%. Music dropped it to that in a few hours though.
I use both the Galaxy Watch 7 and Garmin Instinct 3 Solar. I wear the GW7 during the week and the Garmin I3 Solar on the weekends, when I travel and on vacations so I don't have to worry about charging and I have something that'll actually last during full day GPS tracking. I like the Garmin health tracking but dislike not being able to select the notifications I want on the watch as well as the GW7.
I primarily use my Galaxy Watch 7 for blood pressure so I don't actually have it paired to my Pixel, oddly enough. I tried but the BP wouldn't transfer as it's exclusively Samsung. So yeah, hi, it's me carrying around my pixel main phone and my old Samsung just for Samsung Health.
I have to say the heart rate monitor has been solid for me always, when you compare it the gym and a garmin virtually no difference at all.
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.

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Oura - Oura Ring Series

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Apple - Ultra Series

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Garmin - Enduro 3

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Garmin - Fenix 7 Series

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Garmin - Forerunner 255 Series

Ranked #1
Oura - Oura Ring Series