Whoa whoa whoa, you can tell the difference by just changing the type of filter?
Does this provide documented increases in air flow? I'd consider buying it just for the sound.
Waitlist: #1 M2 CSL
2016 F15 X5 3.5xdrive (Current) - 2013 535i xdrive (Gone)
2008 E92 M3 (Gone) - 2006 E90 325i (Gone)
2002 E46 325xi (Gone) - 1991 E30 325i (Gone)