I had just recently decided to rebuild my A3000T using OS 3.1 as opposed to OS 3.9 which I have been running for the last several years (I have OS 3.9 on my A4000T now). Just to be different, no other reason. I had always used CGX 4 (r5) without any problems, but on OS 3.1 on my A3000T it was not stable at all. I don't why, but it would just lock up when trying to use Picasso II screen modes. I switched to P96 and did not experience the same problems.
Having run the two now they both function similar. I like the screen dragging ability of Cybergraphics and I like the tools that come with it a little better. Both are more than useable. I don't have any of the special requirements that Flashlab has, so I can use either. If CyberGraphicsX has been stable on my A3000T I would have stuck with it.