I have both the Pro and the Comp.

On the comp the diff's are better and the shock tower is more solid than the Pro's.

But I haven't bent the shock tower on my pro yet. And the diff's are still in good shape. One of the front driveaxles has been a little bent and, because it was an european version, it had a plastic spur gear, which stripped.

In general the Comp is a very strong buggy and can take some abuse. And you can get new parts cheap on ebay should anything break.