I have been with TMO since 2003. I got my Pearl about a week ago and it would not stay on any network for long. I had to continuously turn my radio off/on to get it to pick back up. I called customer service. Turns out it was because my SIM card was 4 years old. TMO claimes they have upgraded the SIM cards to work on thier new, faster network. I went to my local TMO store (Actual TMO store, not "authorized dealer") and they gave me a new SIM card for free. They instantly assigned my phone# and all of my contacts, etc. to the new card. It only took about 5 minutes and it seems to have fixed the problem! Customer service even told me that if my TMO store made me pay for a new SIM, I could call back and they would credit my account for the full purchase price!
