I do have an aftermarket intake... but it's so quiet, I wasn't sure if I put it on right. It makes the slightest "whoosh" and I figured I'd hear more of a purge. I also noticed that the shuttering sound coming from my intake is gone.
Can't tell much of a difference in performance so far but in my opinion, I never felt like the car stumbled in between gears with my HKS. Oh well, as long as it's better for the car that all that really matters to me. I really don't need any extra attention with a bright red Evo.