What's the best cell phone service to get if you travel?

I travel alot, I'm talking ALL the time, and sometimes out of the country, so what would be the most realiable service to get for a cell phone? i'm with Cingular right now, and I'm just not happy with the quality of phones thay have. I've had t-mobile and I didn't get service in North Carolina, Mississippi, and other places. May-be it was because the phone was prepaid, idk. But I was tihnking about going back to t-mobile, because the have to sidkick and I love to text. But what do you think? I really like the EnV by Verizion too.
Anyone have those sevrices now and go out of the US with them, let me know how your service is now.

verizon has the best plans as far as calling and texting. they have a number you can call to update your service every 2 months so your always getting service. the number is *228 then press 2 and wait untill your phone restarts. the enV is also an excellent phone. i have an uncle from verizon.

If you dont like cingular then you have to go to t-mobile. The reason is because Cingular and T-Mobile use GSM as their mobile technology and Verizon uses CDMA. The problem is that CDMA is not supported outside the US.

Sprint just sucks.