I beat this mission twice (one on Japanese import and once more on US beta version) and I used Maxima and Kyo. Use the Maxima Scramble over and over again constantly and use Bunker Buster whenever you got the power gauge filled. Occasional Vapor Cannon works good too. For Kyo, use one of the longer Stylish Art.. I think it was the fourth one, but you gotta modify it a little: Front C, C, Diagonally Front Down D (then he does the 88th), then do 75th Kai about two or three times then finish the combo with the RED Kick. Do this combo over and over again. If you want to use other characters, there are tons of different infinite combos... like Terry's infinite Powerdunk. Once you got the timing right, it's pretty easy.
EDIT: Oh one more thing. You gotta try to corner the opponent against the wall at all times. especially if you're going to do some infinite combos.... I just played around for awhile and infinite Zantetsuken by Ryo while the opponent against wall works pretty well...