Lol, I've been to England 5 times, and that's exactly what British people seem like to me. I can't understand what they're saying half the time.
MadTV usually isn't good, but SNL wasn't good between Belushi and Farley, and hasn't been good since Farley. Andy Samberg has made it bearable, but still not great. The last "comedian" to come out of there was Will Ferrell, who doesn't even do stand up as far as I'm aware...just terrible acting in awful movies (Elf? Come on.)
MadTV still exists because it's produced by Lorne Michaels, just like SNL is. As long as he's at the helm, both shows will continue on. I don't think MadTV is an imitation of SNL except for the fact that it's also a skit show. That's like saying apples and plums are exactly the same because they're both fruit.