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 M2CS
(Current): 2016 F15 X5 3.5xdrive - 2016 F30 340xi M-Sport
(Past): 2013 535i xdrive - 2008 E92 M3
2006 E90 325i - 2002 E46 325xi
1991 E30 325i