I came here looking for S4 info and thought I'd give my 2 cents. This show is definitely raunchy and twisted. If you're cool with that, then check out at least a full episode. I read other reviews making comparisons that I don't exactly see. Here's my comparison that others may not see. The level of crass and political incorrectness is similar to IASIP. The style is completely different however. (Nothing can really top Sunny for me). If you are a fan of IASIP, this will probably entertain you.
The kids in the show are very likable. I find most kids on TV to be "white noise" but not these two. However, I would not let kids watch this show. Watch first to make that call for yourself. And Jason and Natalie are really fun to watch!
I disagree with some opinions of S2. That was the absolute best season for me. S3 was a little weak although I loved the setting. I just read a Jason Jones interview that sounds like S4 has a lot of potential!
Random trivia: A lot of season 1 was filmed around Atlanta. (i.e. Salvation, Florida on the show is actually Stone Mountain.) Pretty cool for this GA girl here.