I wouldn't really factor Spirit in to the equation too much unless it's for one of their dirt cheap fares. I've flown them to MCO a few times and their operations are a cluster... unorganized boarding and rude/unattentive FAs. Their "Big Front Seats" are indeed bigger, about the size of an AirTran Business Class seat, but I don't think they have as much pitch. They're also not seperated from the rest of the cabin at all. The times I've flown them to MCO the fares have been in the $30 or less range r/t ALL IN. It's hard to complain about anything in that price range, but flying 4+ hours TCON I would personaly go coach (especially in a B767 exit row) over Spirit in the "Big Front Seat". I really think Spirit only offers those seats to say they have them. They don't do free upgrades for members of their program and those seats often fly empty or only 1/4 taken.