I tried both and they are good. I have AirAid in my charger srt8, and then I installed Mopar CAI in my challnger srt8. IMO, Mopar looks better with the aluminum tube and Mopar logo! in terms of HP I think it slightly over 5HP according to some folks here who really dynoed their rides with and without CAI.
We sell and have installed AirAid intakes here at the shop, so those are what I would prefer out of the two. Yes they will help out slightly on upping the power, it will usually net you around 5 HP (I think they are advertised as 5-7 HP).
I think we actually have a thread going on our AirAid intakes if you want to check it out. We have them at some great prices right now and they are very nice systems. Feel free to PM, call or email us with any questions, or to get special pricing that we can't post on here. Good luck!