I like the advance version,you can have most of the characters late in the game (instead of just the last ones) and it has extra levels etc.

But the DS version is pretty cool too, mainly because there are lots of extra abilities and it's heck of a more challenge.
The only thing i don't like about this game is how many secret items there are and how rare the drop rate is and you have to beat the game 3 times to master it, which is pretty crazy cause you must not mess up.
Don't like those perfectionist types of games that much (also X-2), but beside that, for at least beating the DS version once it's really good.