Here's my take on it so far ...
X2 is running rock solid on my system so far ... and you know all the troubles I had with X1.
The main difference I'm seeing is ... it seems as though I can't run as many effects as I could in X1.
I have a project that is 12 tracks, all audio except for 1 synth and I have to raise the buffers on my audio card because my system can't handle it.
Seems to me I could run a lot more in X1.
I hear no difference in the audio engine, but it is easier to hone my mixes and mastering using the Pro Channel. It's actually quite a bit of fun now that the Pro Channel is working for me. If you recall, it was totally unusable when I was running X1.
So ... the short of it ... I'm loving X2 ... it seems to be a resource hog on my system ... and the Pro Channel problems that plagued me are gone.
I can't recommend it with a clear conscience because my situation certainly does not seem to be the norm, it seems it's giving more people trouble and there's very few posters like me who claim it's fixed most of the problems they had with X1. So I couldn't recommend it without feeling like I pulled a fast one on you Ampfix. :-(
The same people that said X1 ran absolutely perfectly without any problems whatsoever are saying the same thing about X2, so you really have to ignore those people. Everybody knows that 99% of all software has some issues, and we all know about the initials release problems with X1, so you have to question the intentions and agenda of someone who claims it runs flawlessly.
I haven't done any recording with it yet because I have a lot to do at the new house before I can even think about setting a room up, but I have no reason to believe that I would have any problems ... I've had zero recording problems with every version of Sonar, including X1.