Right now I have Verizon Wireless. Before I had Sprint PCS (way before they teamed with Nextel), I've had the same phone number since I was in high school and I'd like to keep it. I was able to port my Sprint number to Verizon, way back. My plan with Verizon won't expire until November 2008, but I'm just doing some research right now. I want to test out T-Mobile and AT&T in Colorado -- I hear every carrier has certain trial sessions to test out their service -- so this is what I want to do, see which is the best for me. My question is, my phone number is eligible to port to both networks (T-Mobile and AT&T). Say for example, I want to test out T-Mobile first, and port my current number to T-Mobile but then decide it's not for me within the trial period. Will I be able to port my number to AT&T and test out their service? I hear T-Mobile is actually better than AT&T in Colorado, so I may switch back after AT&T's trial period. Will there be any problems porting my number back and forth? I *REALLY* don't want to lose this number. Thanks.