Well I will tell you about my expierence. I had bought a G1 from T-Mobile with out upgrading, and had a
Sim card that was about 2 years old from a T-Mobile
Shadow. The phone did not pick up a
3G network at all, and the store said it was something to do with the
Sim Card. They swaped out my
Sim Cards and it worked beautifully. I ended up returning it because I needed the 400 dollars it cost me. Stay with me, because I got more.. lol...
I switched my plan back to the Shadow and all that stuff, and ended up coming across a G1 on Craigslist for 200 cash. I went a looked at it, and stole it (lol, it was a month old no scratches, so yeah it stole it for 200) and poped my
Sim in (the new one). I had internet access, text messaging, and all that I had on the Shadow, but I could not access the Maps search, Andrioid Market, or anything that had to do specifically with the G1. I did add that on, and it was 24.99 for G1 "Unlimited" date and 400 text, which is good for me.
So I guess for all my rant, and I hope some of this will help you decide, the G1 was an added on plan, so I almost bet you can just add on the 24.99 G1 plan with 400 texts, and be good to go with your old plan, and not loose your min's.
