Have 46mm galaxy also. I will probably change to the active 2 44mm when i find a deal
Goodnight mode and airplane mode on at night will get you quite a bit more - sensors still work, it's just not hunting for your phone all night.
Yes, I currently have a galaxy watch 46mm and I get about 4 days on it. I heard this is 2 days at best. I have an active 2 on the way (finally) from the recent £101.98 deal so I can't personally justify the extra for this watch 3.
The bad reviews on battery life are concerning.
I have the Galaxy Watch 4g - should of made that part clear. :)