Working on (possibly) setting up a new account with AT&T using my corporate discount. What I see on the corporate side is something called "DataPro Enterprise 3GB for iPhone 4S." This costs $45/mo minus 25%, for a total of $33.75. But then on the public AT&T site, I see "DataPro 3GB" for only $30. Anyone know the difference between these? The reps on AT&T's online chat have absolutely no clue what I'm talking about and cannot explain the difference. I'm just wondering why one costs more. Thanks for any help.