T.S.
For me, Nextel was the only service that always worked. I tried Sprint, TMobile, US Celluar and paid $$ to transfer out of a contract to Nextel (which is now with Sprint). The problem is that Nextel was SOOOOO expensive for my and my husband to be on. My work offered to pick up my cell phone bill if I switched to Cingular, I did and I have very few problems at all! Both my husband and I have the RAZR and are happy with it. BUT, beware as I have heard other people that have problems (my sister and brother, actually).
Good luck.