I've read that a 3g running 4.2.1 and baseband 5.15 can be unlocked but the consequences or losing the GPS function scare me. Theres a 3g 8gb for sale on CL here for 150 in excellent condition. Problem is the owner updated it. SHould I risk buying it but not having GPS or keep looking for one with a lower baseband? BTW I'm on T-Mobile so the 3g or 3gs doesnt work anyway.
If it were up to me, I would not buy it. Unless the owner can confirm the bootloader is 5.8 in which then the baseband can be downgraded to a safer baseband to unlock. If not, look for another deal if possible.