Luigi. I always play as him, and he's my favorite Mario character (even more so than Mario himself)
Sports Illustrated Kids' Video Game Issue said that a Jaguars running back (who is also the best video gamer in the NFL) played a game of Mario Kart Wii against on if S.I.'s child reviewers. The running back played as Luigi and won the race. It is stated in that issue that the running back was an excellent Mario Kart racer.
By the way, in Mario Kart DS, Shy Guy is, in fact, NOT a hacked character. You play as him (and only him) when you are the download end of the Download Play multiplayer.
I do like using the Dry Bomber in Mario Kart DS. If you beat the game 100%, any character can ride any of the karts! Even Bowser on the Dry Bomber! I thought he couldn't fit into that thing lol.
Minecraft Clan: Swordmasters of Hyrule / Skype: thesupersonic233