Doh! I missed that! Sorry. And at first I thought I'd missed something there, but I paid £79 for the X1 Producer Expanded to X2 Producer upgrade, whereas the X1 Producer to X2 Producer was £99. I'm glad I cleared that up in my little head.
As or X2, and I've said this a number of times over the last few days, I'm over the moon with it really. I had hardly touched X1 though, jumping from Sonar 6 Producer to X1 in the summer.
For me, the highlight is Automation Lanes and they are allowing me to explore that avenue more. I used to find drawing envelopes a bit of a pain previously, but dedicated lanes, and the new draw and edit methods are brilliant in my opinion. I like to create old fashioned synth stuff like Tangerine Dream for instance and being able to tweak all the various parameters in Absynth and Z3ta opens up new avenues for me. I know you've always been able to do this in real time, but I prefer to do this task after I have my main synth tracks down.
And that's just one thing. There are other enhancements too, like the way you can draw notes in the PRV now, that make the "composing" process a bit better for me, and the way I work.
Yes, I've had a few issues, but as a hobbyist I've not come across any real show stoppers yet.
At least with the boxed media you don't have any issues with corrupted download files ;-)