I've also got mixed feelings about it so far. This is my 4th day using it. 2 minutes ago I noticed it got disconnected from my phone and when I took it off the Samsung Duo Charger, I got the overheating message. So not a great start. I used a Watch Active 2 before this and I have never had this sort of issue with it.
The battery life is indeed less than I expected to be honest, but maybe that will be sorted out by future updates. I do get more than 24hrs but maybe the usage is different.
I've also noticed it doesn't count the floors properly. I only got about 2 floors counted yesterday, but in reality there were a lot more.
I'm also having trouble finding accessories for it. No straps, no screen protectors...