I just switched to Cingular because I'm hoping to get better signal. As it is now with T-Mobile, I have 0 signal at home and very weak signal at work (goes in and out of service). So, I figured that it couldn't get any worse. We'll see what happens in my situation once I actually get the phone. I chose another SonyEricsson phone (T637) because I love my T610 and I can unlock and upgrade SE phones.

The only downside that I can see to Cingular is most of the phones you get from them are 850/1800/1900MHz. Since you're talking about newer Motorola phones, you have quad band which allows 900MHz reception in europe. I only go to europe about once a year (for the empeg meet, of course), so when I go I will probably just bring my T610 with me which has 900/1800/1900.

If I were shopping for a wireless provider today, I would go with Cingular because of the merger with AT&T. From some coverage maps I've seen on Howard Forums, it looks like they absolutely dominate the metro NY area now compared to T-Mobile. They also support EDGE which you can use if you have a data plan and your phone is equipped. The SE phone I just bought isn't but at least the ability to use the network is there already. I used the GPRS connection through T-Mobile a lot when it was free. Now that they killed that (it seems since I can't get on anymore), I really miss it. I took Amtrak business-class (110V power at every seat) from Providence, RI to New York a couple months back. I was surfing the net almost the entire way through GPRS. That was awesome. I am tempted now to try it on a plane while keeping my phone in my pocket out of sight. It's too bad I'm too paranoid to actually attempt to get away with it.