BMS is cool, sounds amazing and really enhances the standard 'noise'.
I am waiting for the Riss Racing intake as I have heard good things.
Not sure about the BMS dual cone, as there really isn't that much difference between the single and dual.
Listen to this cheezy noob on YouTube
The review is iffy, but you will hear th sound.
Current: 2015 BMW 640d Coupe Imola Red with Ivory leather and 20" alloys
Previous: 2013 Mercedes C63 Coupe, 2011 Mercedes C350, 2010 BMW 135i Convertible, 2008 BMW 135i Coupe, 2006 BMW 335d Coupe, 2006 Honda S2000, 2003 Honda S2000, 2003 BMW 330Ci Convertible, 2001 Audi S3