Reply to S4 Helps?

Hello, just got my new S4 in and its freakin sweet (especailly compared to the Mixtrack ive been using for over a year now) but i was wondering, people say that they love to use the S4 and Midifighter together (had a classic for about 6 months now) but the S4 feels pretty complete to me, what have you been using your MF for?

Oh and my sound keeps kinda glitching/cutting...any tips on how to stop it?