Just curious on what you all might think about this set up. Do not have a whole lot to spend but really want to up grade my exhaust on my 2007 Street Bob. I put Vance & Hines Shortshots Staggerred Black and a Fuel Pak on so far. Any thoughts or experiances using a K&N Air Filter Stage 1 kit RK-3909 with this set up? I have heard mixed reviews but was looking at this not only for more intake but maintaing that stock look as well.