I'm really new to the whole Jailbreak Unlock thing with the iPhone, but I agree with you, this Negri unlock is very expensive especially if you compare the price with the Gevey sim and the Rebel Micro SIM-card, I don't see the point of paying 3 times as much. True, u have to use the adapter vs permanent software unlock (but we don't know for sure it'll be permanent) but I don't think is an issue, if it works it works, u get an unlocked iPhone either way, and with the sims u can update FW if it gets locked again and there's no record in a database or anything.
I need to unlock my phone because i'll be traveling a few times a year to south america and I would like to hear more about the Gevey vs Rebel, I read that the rebel is better, and I don't really need to jailbreak.