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

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Ticwatch pro 5. I got one for 100€ on amazon and it has amazing battery life (3-4 days), very good health tracking and a dual display - the second one looks like an old casio. Full Android Wear compatible and very fast. New they were 350€, now they're a steal.
Fair play to Google. Rocking a TicWatch 5 pro and I charge it once every 4 days.
TicWatch Pro 5. Love the thing. Dual layer screen - looks like a cheap LCD watch until you wake it up.
Smooth as hell and runs for days
If you’re okay with something bulkier, the TicWatch Pro 5 is often recommended — great battery thanks to its dual-display system and full Google Wallet support. Also, OnePlus Watch 3 is getting good feedback for balancing Wear OS features and battery life.
What is it like on workout detection? My Samsung Galaxy does a far better job than my Ticwatch pro 5, but the battery on the galaxy watch is terrible in comparison so I end up swapping watches depending on what I'm doing. Even on a treadmill with both watches on, the galaxy tracks better despite the treadmill being made by Mobvoi! It would be nice to have a watch that does both.
I would check Quantified Scientist Youtube channel's latest video and buy the highest rank on sleep tracking chart that's within your budget. Another thing to consider is metric, if you just need correct total sleep time tracking (like most people, because it's the most important metric to nail) then many watch would do. However, if you need correct HRV, Spo2, Deep sleep and REM tracking then you might need to spend more. My Ticwatch Pro 5 track my total sleeping time and HRV like a pro, scarily accurate (using Sleep As Android, not native feature which is trash). However, when it comes to deep sleep (and maybe REM too) it's a bit of a let down. It fails to detect some deep sleep period so my deep sleep percentage is often a bit lower than expect. Maybe consider OPW2/3 for better support but I think it has the same accuracy. The best way is to save up for an Oura ring, but that's a bit expensive.
Does anyone track hiking with the watch? My walks are often 4 or so hours, I'm interested in how well it does on those, my Ticwatch Pro 5 can handle it but sometimes drops 40% of its battery on a long walk.
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