I've searched around a bit and can't seem to find a definite answer. I'm new to Subaru's with my WRX being my first owned. I really would like to hear the turbo spool and the bpv...I was thinking about the Rallitek drop in filter, or does that not really make it that much more noticeable? I was looking at a CAI from Rallitek too, but figured if the drop in did what I wanted I could save myself some $$. I don't plan to go crazy with mods on this car, just want to get a little bit more out of it. I would like to keep the car as close to "stock" as possible. Any help would be appreciated!