No answer in over 24 hours, and I can't tell you either, although I'd guess that you might. (I know, I'm a big help.) Try asking in the Straight Talk section of Howard Forums. There are a lot of people there who have been on AT&T through ST for a while.
Although you should be aware that AT&T MVNOs have been having data problems for a few weeks now. Something AT&T is doing, most likely. If data (other than wifi) isn't too important to you, no problem, but if having a data connection at all times is something you need, stay with AT&T directly until this mess gets straightened out.