I just installed WSP Y-Pipe and PR CAI and it is awesome. I installed the Y-Pipe two weeks ago and it sounds great because it is fairly quite. I am not sure what everyone talks about the bees in a can, but I sure don't have that sound at all with the warpspeed. Great sound and great performance gain. Yesterday I installed the CAI, and boy did I miss the sound of WOT, it is great (had it installed on my 2000 Civic Si Vtech). Nice performance gains, very nice! I am not kidding when I say this, when I come off the line I can't hardly keep the car straight, I am running the factory tires and wheels, maybe I need to upgrade. I definitely recommend this $425 combo to anyone. Just one bit of advice, make sure you bend the metal hanger back off the Y-pipe or it will rattle and rattle your whole dash.