I have looked around, and so far not sure if it is my phone, or the network. I suspect it is the network, but here goes:
I have an iPhone 3g 8gb in the UK, bought on O2 but unlocked using Blackra1n to use on T-Mobile UK. This went ok, and the unlock works fine, however, roughly 90% of the time, I only ever get a GPRS signal (T-Mobile (as far as I am aware) dont support EDGE) so if I cannot locate a 3G signal I drop right down to GPRS. I was wondering if the unlock does something to make the signal, not so strong if that makes sense? Usin O2 in the same locations (before unlock) I had 3G signal almost 95% of the time - now I know they are two totally different networks, but the signal strengths seem worlds apart.
I am also wondering, in the UK we can pay to unlock iPhones now via O2, if I do this officially will the signal strength improve do you think?