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

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Garmin FR 570 here, the battery is ok but it only lasts for 5/6 days max if you are active and use gps...
IMHO you should wait another 3-4 weeks since there are rumors on a Venu 4 coming and that might push price lower. Also in the meantime you could try to test existing models on your hand - generally smaller models are much more comfortable but larger models are easier to see, have longer battery life and often have better GPS. Also another model that IMHO might be better than Venu 3s is the latest FR570 (small if you want so - compared to Venu 3s brighter screen and better GPS) and still has the ability to take calls (like Venu3/3s).
For Venu you have 3 and 3s, same generation but 3s is the smaller one for ladies (and with some ladies color combinations). Also if you want to have the absolute best (with calls) at this point probably Forerunner 570 (also 2 sizes, has brighter screen, better GPS and separate flashlight). EDIT: and Vivoactive 6 also is AMOLED.
Easy FR970 Keeping smart features aside that AW gets with its apple integration. You don’t know how much AW or any apple watch in general lacks when compared to a mere Garmin FR 265. Let alone me FR570 or 970
Only thing stops me from buying garmin is value preposition. Old models from garmin were priced right. The newer models are priced insane when you also take into account the built quality and software experience. For example : a $1900 fenix 8 pro/fenix 8/forerunner 970 and 570 has a good build quality, but the software is very laggy, start the activity with maps and spotify running it will lag like anything…as per garmin support its expected because of low power cpu and ram. Again if you compare with apple watch ultra the ultra’s build quality is better, you can use full lte and with ultra3 you also get satellite support, fenix 8 pro only supports handful countries and the reception is poor because it uses a different technology and not exactly satellite communication… check YT reviews on this. There were reports where the bezel and “plastic” body of forerunner 979 … (a $750 watch) fell off and thankfully they were in warranty.. i wonder what happens of watch is out of warranty. Venu 4 construction also looks poor to me. Although they use mix of steel and plastic. AW on other hand are built of a single sheet of aluminum Or titanium… ultra which is cheaper than fenix 8 has better construction imo and will last longer. The sw experience with aw is also good. Buy a healthfit app and you get almost equal training insights as provided by garmin. Also i got to know by developer the are redesigning their health insights in the app which will be at next level. Andit costs just 6.99 one time payment. Additionally you also get true satellite, lte, fall detection etc. the list goes long. I don’t need to mention hr sensor accuracy and sleep tracking.. they are the at the top, you don’t need a chest strap even for hiit and gym workouts when using AW So yes today i feel garmin is lagging behind if you keep the battery life out of picture.
Still one of the best when it comes to performance/price. Performance is super nice, long battery time, many functions. But ofc if you have enough money, go for a newer model like FR 570. I dont know much about swimming. Probably the FR 9xx is better for that.
The format of that 2s looks like the perfect size imo. Doubt the 1mm higher sizing of the Venu4 would look much different. Probably your best bet as feature wise it's pretty much equal to the 570, with added ECG and flashlight, only lacking in the amount of buttons (really useful though when running) Can always go to a store and try a few out (if you have one near you with garmin watches).
I have both. Please do yourself a favor and buy a Garmin. Period. And don't be one of these guys who keeps pondering this every day. Waste of time. Apple Watch (Ultra) is only worth it for most people if you have family that is heavily connected in the ecosystem and you call a lot from your watch, etc, receive messages and photos on your watch and reply and so on. My guess is you will be happy with Garmin. If you want the watch as a smartwatch for notifications, calls, photos, emails and some added fitness features -> AW. If you want a great fitness watch with very good battery life and smart features depending on the model -> Garmin.
This is oversimplified but true imo. By the way, prudent question to ask yourself before overspending is what you actually want. Not what smartwatch / fitness watch you might want. Maybe you're fine with a Casio, maybe a G-Shock. Maybe a cheaper fitness watch like Amazfit. Decide what you want and buy accordingly. Even though I have an Ultra 3 and a FR570 I like to wear cheaper G-Shocks or mechanical watches a lot. You will know what you need - and don't worry there will always be a next better AW or Garmin, so you are not missing out if you don't buy the top tier model right now unless you do need specific features now in your everyday life.
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