I've always used K&N oil filters and my UOAs shows good wear numbers. When I did my last oil change I used a Puralator PureOne filer, known for its filtration rather than flow since I didn't have a K&N on hand. My friend who has the same car (Honda S2000) has a S/C on his car and uses the PureOne. On his last UOA, we had the similar wear numbers except for alumninum. I had 4ppm compared to his 31ppm. His 10W30 oil also thinned to a 5W30 weight where mine remained at a 10W30 weight. Can the supercharger be the cause of the high aluminum or the more restrictive filter? I have a K&N on hand now, should I just change back to the K&N? I've had the PureOne on for about a week. Oil pressure is pretty similar between the two filters from what my oil pressure gauge tells me but I think my engine sounds a bit louder with the PureOne on.