MADTV was unquestionably the funniest skit show ever aired on television. So many of their bits from 10-20 years ago still hold up very well today, and Debra Wilson is a gift from God in terms of comedy. The woman did some of the greatest, most hysterical impressions I've ever seen, and the rest of the cast is great.
Aside from Tina, Mayah Rudolph, and Kristen Wiig, SNL was never funny. Kenan Thompson and his repetitive Black jokes are tough to sit through, especially since he's been doing them ever since he left Kenan and Kel, and I'm sorry but Chris Farley's old "LOL, I'M SO FAT AND UGLY!!!!1111111!!!!!!" skits are beyond dated and wouldn't be looked back upon as fondly if he didn't die.
(along with a few other shows)