When the iPhone was AT&T-only, everyone (including me) complained about AT&T's network - dropped calls, weak signal, etc etc. Now, iPhone is available on 3 major carriers and Sprint users are reporting unhappiness with Sprint, while Verizon users are not that much better except for not many dropped calls. With the 4S on AT&T's network, I'm getting good reception, no dropped calls, decent data speeds. So, the issue could have been with the phone itself, that's been fixed now? Or do AT&T customers using other phone models also complain about dropped calls?