D'oh, my mistake, I was looking at his GCL numbers, not his NOR numbers...
Hard to say anything without anything but the numbers in front of me, but he doesn't seem to be walking anyone so far, so that's a good thing.
http://www.milb.com/milb/stats/stats.jsp?sid=milb&t=p_pbp&pid=571616 is about all I can use at this point.
Personally, I would hope that he stays as a starter as long as possible in the minors and convert him to a reliever if and when that's deemed the best thing for him, it's pretty rare for a guy to move all the way up the ranks as a reliever, usually they're a starter for a bunch of levels and converted around AA/AAA. Of course, that's not always the case.