Use Cingular. Blows.
Tried TMobile. Tterrible.
Have Verizon. It's the best one of the three! Sucks.

I have never had good service inside my house from a cell phone. Don't expect it.
Walls. I hate walls. They provide nothing. They just block service.

Personally, I would wait until AT&T starts another cell phone operation. They sold their people off to Cingular, but I saw someone get reception in the mountains out in the middle of nowhere back with AT&T.

For me, it's all about reception. If I can get good reception in most places, I don't care how much it costs, I will take it. Verizon has been the best in that regard for the moment, so I use them. Coverage area and roaming are really important too for me because I go alot of places. Verizon does that pretty well.

Land line...how I love you.

I have been using t-mobile in the boston area as my only line for awhile and have had no problems. of course, voicestream/t-mobile started out in the US in sf/ny/bos. they have a reception/coverage map at . t-mobile is GSM, so you can use any handset you want - i.e. if there's some sweet new phone out in europe or asia, you can buy it unlocked (after refinancing your mortgage), drop in your SIM card, and use it.

cingular is also GSM, but the phones have to be quad-band, which may or may not be hard to find.

but yeah, i would say just get whatever gets you good reception, unless you really care about the phones.