I got a $30 Swiss Army bag from Target several years ago. It fits a 15" laptop just fine and has room for two textbooks in another pocket. I feel like I've gotten my money's worth out of it and would recommend it in a heartbeat.
You'd be overpaying at those prices, unless you care about the label. Go to Target, check out their luggage section, grab a $30 bag and go on one hell of a bender with the savings. That will make you far happier than a $220 messenger bag will.