I used PSP 9 before X2, so I can't give you a definitive answer. I deferred getting either X or X1 (is that what they called PSP 11?), because I'd read complaints about balkiness and instability.

With one or two exceptions, I find X2 to be faster and more stable than PSP 9.
Here's a list of features offered in X2, in case having them handy would be helpful to you: http://www.digitalcamerareview.com/d...p+pro+photo+x2

The only place that I have frustration with X2 is in the use of the Curves adjustment. If I'm careless about trying out too many different adjustments, or only several adjustments but very big ones, the whole program can freeze. Nothing but shutting PSP down with Task Manager will get me unstuck. Consequently, I try to avoid careless over adjustment in Curves. Also, I save my work again before Curves adjustments when I remember to. But that's the only situation so far that's given me trouble. Other than that I'm glad I finally took the plunge.

Maybe others who've actually used PSP X will be able to give you more detail.

Good luck!

S.