I'm guessing this is a some sort of scam, but there's companies offering to JB & unlock the 3GS with iOS 4.0. It seems way too 'convenient', and I thought all JB stuff is free. If they're charging, do they have more manpower to crack iOS 4.0 first?.. How do they offer the guarantee without getting sued? To answer my own question, I'm guessing they take the money, see if any of the free cracks work, then if it doesn't, they make plans for a transfer after a set period of time, and if nothing else, "borrow" your money for free, and keep the $ from the phones that do work with the freely available software.