Oiled foam (AMSOIL,UNI)	Paper	Oil Bath	Oiled Gauze (K&N)
Large particle efficiency	5	5	5	4
Small particle efficiency	5	4	1	2
Airflow capacity	5	2	3	5
Dust holding capacity	4	2	5	2
Load up characteristic	4	1	5	1
Backfire characteristic	3	2	5	3
Cleanability	4	1	4	3

As you can see, K&Ns are great for airflow, which is what they were designed for. Their original application was on racing engines, where airflow is important and ultimate engine life was of little consern. They are not as good at filtering as paper or oiled foam types.

 Ed Hackett   edh@maxey.unr.edu           The Desert Research Institute 
 DoD #0200  WMTC  BMWRA  DIOC             Reno, Nevada   (702) 673-7380   
 KotLS  KotLE  DotD #0003            I'm not really a chemist, I'm just one of
 900SS  K100RS  501 CAMEL            them motorsickle sonsabitches.  __=o%AMP;o>__