I don't really think there is a reason for a repeater. the advantage of a repeater is that it saves having to get rapid reload, however rapid reload is a prerequisite for a lot of other cool feats later on so you might as well get it anyway. then theres also the fact that the repeating crossbow is an exotic weapon so you're not really saving a feat and as far as I know the only class that class thats proficient with repeaters right off the bat is the bolt ace, gunslinger archetype.
I personally think that a good house rule to make the repeaters actually worth it is to remove the need of a free hand to pull the lever that lodes the next bolt. but yeah, as it stands I can't really see a reason to get a repeater.
Inquisitors have proficiency in repeating crossbow.
oh, I've just realised that I somehow created a new thread instead of replying in one. I don't know how I even did that. if a moderator wants to delete this please do.