Don't buy it. It's pants.
Instead, get a PSP and Pulse, and you can play the best game in the entire series wherever you like.

I should mention that I'm more or less a Pulse fanboy, and that my views are therefore questionable, though.
If I were to put that aside, I'd agree with what Temet said; it's a broken mess online now, but well worth getting if you're playing only/mainly offline. Nice looking game, plenty of content and variety, and plays nice enough.