I've got an RC30 build G1 that I've had for just over a month. Up until a week ago (1/22) I never lost my 3G connectivity. Ever since last Thursday, my phone will lose it's data connection after it's been on for 15-30 minutes. I can either power cycle the unit, or sometimes, switching from 3G to Edge and back will reset the connection. I've tested the unit in multiple locations ranging from Denver to Boulder, and it doesn't seem to have anything to do with signal strength. I've called TMO advance tech support and have an active ticket, but they keep putting me off and extending the estimated date that this will resolved.
TMO told me on 1/24 that there is a known issue having to do with G1 data connections, but they expect that it would be resolved within 24 hours. It's now the 28th, and they told me this morning that they should know something in "a week or so." They offered me 100 extra minutes for the inconvenience, but this hardly makes up for no data service...
Is anyone else having this problem? If so, please be sure to call TMO support at 1-877-816-8601. The more people who complain, the harder they will work to resolve these issues.