[quote name='trunks982']is the PS3 version good? i know the PSP version sucks and the Wii version is really good.[/QUOTE]
Yes, the Playstation 3 version is supposed to be the best. The Playstation Portable version wasn't the same game. They chopped it up or whatever from the Wii/Playstation 2 version for some reason, and changed how it played. From what I remember of the reviews it's the one you want if you're picking between platforms, although I don't think it's supposed to be this gigantic upgrade from the other versions or anything, just basically the 360 version with some extras (which was already not a HUGE upgrade from the current gen versions from what I read).
$20 seems like a good price to me, I do kind of want to play it.