The build quality is about the same. The screen on the 3000 is better. I like the fact that all four buttons around the cursor pad are programmable. Have four hard buttons along the bottom of the screen will be nice once they get a software/firmware fix out for the current problems which prevent all four buttons from being programmed (currently only the middle two are available). The backlighting on the 3000 is nicer than on the 5200.
I like the way the 3000 feels in my hand better than the 5200. The case has a slight taper that helps it nestle down in your palm. Neither the 3000 nor the 5200 sit on your leg as well as the originals.
Both the 5200 and 3000 are major improments on the original formula. Both have larger screens. Both have default user interfaces which can be overridden easily. Both allow you to edit the entire screen. Both make me worry about the cup of coffee sitting next to it on my coffee table right now.
