I run a big airaid 6" inlet filter that i adapted the 5" - 6" intake on my s472 kit for. My first impressions of looking at the filter was that it looked great to me. I live in a new construction area and there is constantly tons of dust blowing around, ive had that filter fairly plugged up. Pull it off and wipe the inside of the pipe with your finger and its clean as a whistle. Took the intake off and the compressor is also clean as a whistle. It is an oiled filter tho...I personally like oiled filters better than dry filters. I have zero complaints with my airaid filter. Im not sure what the part number is but I believe it is a filter from an airaid intake for a 6.4 power stroke. Seeing is believe for me...if I see signs that the filter is not up to par, I will switch. But as of now, I am content with it.
Compressor after several months with the airaid filter. Clean as a whistle.