The cobb filter is just a green filter. I can attest to the noise difference. Its really only noticeable of the window is down and the radio is off haha. Compared to the stock filter its waaaaay less restrictive.
I contacted cobb/greenfilter and you can use K&N cleaner oil. I added my new cobb filter yesterday and went for a 80km drive on Australian country roads with it and it does breath better. I am now looking forward to installing the GGR induction hose and seeing what it adds to the sound and air mix.