I was really happy with the previous OS also, pros and cons to both sides, the biggest Pro for me is I use the lock screen only for Samsung pay and now the keyboard is bigger easier to use, on the previous OS I like the way the watch faces scrolled before, you can still scroll just differently, but now you can also share watch faces, I saw somebody at Jack In The Box with a S3 and they had a watch face I liked but I didn't want to ask him to send it to me because I didn't know the individual.
I would say upgrade and then restart your watch after the upgrade to clear the catch it's been smooth for me no issues