You're correct, the main benefit to my unlocking service compared AT&T is listed below:
Less wait time (typically unlocked in 24 hours vs. 5-7 business days)
No application denial (Any iPhone that meets my requirements will be unlocked or you get a full refund)
Unlock for iPhone's whose contract has not yet expired/terminated (AT&T will not do an unlock for iPhone's still under a contact)
If they deny me, I'll PM you. Not in a hurry, it's sat in a draw for a month.