Personally, I avoid Culpepper for fantasy. He's too hit or miss for me. Last year he rocked it, but the year before left many a Culpepper owner out of the playoffs. I just think he's too careless with the ball. Last year may very well be the first of many good ones, but I'm not convinced yet.
Two years ago when I had Vick, I won my league title and will pick up Vick again if I can. He's too explosive and too dangerous not to... especially if you have a well balanced team. I'd take him over a Brunell any day.