I ran my show from Dec. 10 with only minor problems on 2.5.0.8. I had four instances of the show crashing: not Vixen, not the computer; I'd get the dreaded Com Port error, which I could cancel and then use Restart Timers and all was well again.
This was 64 channels. I went to 2.5 to gain access to the dimming curve feature, which I ended up not using, but once I'd upgraded and wasn't really having problems, I didn't see the need to go back.
There was one other problem with 2.5.x that I noticed: the test channels function didn't work. I merely launched 2.1 when I wanted to test channels.
I believe KC has said that he's going to skip any more of the 2.x series and go straight to 3.x. He has always provided sequence-updaters to bring users from one level to another if there's been a file-format change, so I'm sure he will in the future.
The impression I got was that the 3.x series will have separate applications for sequencing and show playing (but maybe I just dreamed that one up).
\dmc