on my NA before settling on the HKS Sport. It looks very close to stock (except much nicer tips) and sounds perfect. Quiet in the cabin at 1500-2800 RPM (the dreaded resonance zone) and nice aggressive sound on hard throttle. I found even the Borla to be annoying after a while, and I've heard the Stillen resonates like a sumbitch in that RPM range. I never tried the Genie, but I understand that's fairly quiet as well. But it's single tip.