Watch Wai's beta's demos. Sonic acts crazy in Hill Top Zone. Then, watch the demos in drx's beta. They're pretty much the same, and Sonic isn't acting crazy in drx's. He jumps on the teter totters in drx's perfectly, and makes the same motion in Wai's beta. I doubt he'd go to all the trouble and edit the levels EXACTLY like the demos when you leave your game unattended. Not to mention, having to make the levels like some of the screenshots in the magazines.
I can't really say much in his defense since I haven't looked at the code for either games, but I do believe him. (Plus, he seems like a really loyal person to this community with lots of friends, and I don't think anyone would purposely steal from their friends.)
Edit: Heh, the thing that says "YOU ONLY HAVE SO MANY POSTS LEFT" in red is gone for the trial member thing. =P