Had an exchange with Tim tonight about the Big Air Kit and he gave me permission to post it:
"I posted some on Facebook comparing the modified air box and big air but I can’t find the screen grab. I would have to dig thru the dyno runs and find the triple threat. I think the Big Air stacks cause you to lose about 14HP vs the modified air box in the mid range on average. Even more comparing it with the triple threat. I developed a reflash that alters the throttle opening rate and gains close to half of that back depending on the exhaust system. The triple threat is probably the best all around mod, but its hard to do and most people screw it up and the inner stacks hit the filter or it just looks like ****. Big Air is easier and probably makes 3 - 5 or so HP more on the top end but that also depends on the exhaust. The BA gains get bigger with race gas. That’s why I tell folks that go to the track and want results, Big Air is what I run."
So there you have it, right from the man himself.