In my situation, it's because I have oversized air runners with no provisions for stock style (pipercross) air filters. If I had a choice, Pipercross would be the filter to use.Looks like you actually reduce the filter area by a factor of 2 or so from a stock filter (or close to it, anyway... It's a guess...). What gains do you expect to get from these? More filter area?
More air flow?
I'm not trying to be sarcastic, I want to better understand why to use these.
And, sorry, I plead ignorance... why not Pipercross or stock? (Don't even know Pipercross) and I've found that stock doesn't suck...