Options for using an ATT iPhone on a prepaid plan?

[wurm]

Here's a question. As I wait for my AT&T unlock to come through on my newly acquired but as yet unused iPhone 4s, might it make sense to buy a month of a prepaid Pure Talk or StraightTalk sim, just so I can use the thing while I wait? The only downside I see is the changing of the phone number...and that's a big downside. I wonder if I could just have my existing number forward to the new number. Hmmm...