Basic Shredder is an okay figure, but he is nearly impossible to stand, even with a proper stand and against a wall. Super Shredder stands better, but he's in bad scale, and his helmet is the wrong color. Still, I like the Super Shredder mold, so I will eventually get him.
What I like to do is compare figures here:
http://www.tmnttoys.com/figures.html
At least after some research I can make a better choice of which order to properly collect certain figures.