I don't know if MadTV is still as good as it was in its first few seasons, but when it debuted it was leagues beyond SNL; that said, considering SNL has been running foul for a near endless amount of years, that's perhaps not the best comparison.
Everything MAD-related was inspired and partially founded by a french guy, René Goscinny, the funniest writer that ever lived, and the greatest comic book writer ever, by the way.