I have had a T-mobile pay-as-you-go account (voice only) for the past few years. Now I'm planning to get the Samsung Exhibit II 4G phone from Walmart and their $30 plan (unlimited web and 100 minutes of talk). I want to port my current T-mobile PAYG number to the new plan, but I've heard that the Walmart $30 plan is only for new accounts, and porting existing T-mobile PAYG numbers is not possible. Is this true? If so, I was thinking to instead switch temporarily to an AT&T PAYG account and port my current number to AT&T, cancelling my T-mobile PAYG account. Then I would sign up for Walmart's $30 plan, and then port my number back again. Would this get around the restriction that Walmart's $30 plan is for new accounts only? Is there any minimum amount of time required before switching carriers and porting my current number? In the worst case, I was thinking to get a new number with the Walmart $30 plan and then port my current number to Google Voice. One issue that I'm a bit concerned about is I've heard GV has some latency (delay) issues when talking on the phone, and that would be annoying. Does anybody have experience with this? Thanks in advance.