I'll probably only use X2 for brand new projects
This is, in my opinion, a very sensible course of action.
The only problems I've had with X2 (& X2a) has been with projects started id X1 (or earlier)
For brand new projects, X2a is, at the moment, 100% reliable & stable
There are bugs, but none of them are showstoppers and there are workarounds for all of them (as far as I can see)