I would go with a hefe. 7 days in the fermenter and two in the bottle and our recent one was good. Sure it got better, but it was really good AND carbed up even then. I think you said you were taking kegs to Bonnaroo, so that's not really an issue for you. I've not used kegs, so I can't say anything about that.
We also recently did a mild. Now it's possible we over hopped and under primed, but it really did take about 4 weeks to condition up properly. We were kind of dissapointed with it last week, but last night we tried it again after a week and it had carbed up a bit more (still really "authentic" carb levels!) and really gotten good. We originally did this style 'cause we thought it would be fast. Faster than an IPA? Yes, faster than a hefe, no.
I now think only wheat beers are actually fast.
Plus, if it's hot, you'll be glad to have the hefe.