If you're asking me, outdoor sucks in every way compared to indoor. The band isn't lit up properly for the first half of the show, there can possibly be bugs or whether, you can see everyone in the entire audience while it's light out, which can be distracting from the show, and worst of all, sometimes the sound is too quiet! Like at the Greek in LA, at certain points there I'm thinking WTF I paid money to hear the band play and it's not even loud enough to hear over the people talking next to me??
However it only sucks in comparison. I have nothing against going to a show just because it's outdoors. I saw the tribute band Bostyx outdoors in a park and I was standing right up front against the front gate thing and that was probably one of the best shows I've seen.