been with sprint for years - their signal quality in most areas is excellent, sound quality is the best I have used, and I can roam off their network when in rural areas (extra charge, or pay $5/m for no charge roaming)

however, sprint's customer service is, well, lacking. As long as I don't need to talk to them, I am fine.

Then again, nothing compares to Cingular. This is bar none the worst company you could imagine. Their signal is weak, voice quality is poor outside certain urban environments, and their customer service couldn't even be described here without me violating FT TOS. I had them for a 30 day trial through my employer and dumped them as fast as I could.

When I called to cancel, the customer service 'person' said she needed to put me on hold while she checked my account - but she didn't actually put me on hold, she just put the phone down and I was able to listen to her personal phone conversation drone on for over 5 minutes (talking about family, kids, boyfriend, etc.) - after 5 minutes she returned with my account information and said she could not process my request and transfered me onto another department. This is only one example of the many types of conversations I had with them while trying to get my account setup. It was a complete nightmare from day one. Usually, I would just end up wasting 30 minutes of time while they transferred me from group to group trying to find someone who could answer the most basic question.

Depending on your international travel habits, I would recommend Sprint as the best choice for a domestic carrier.