Went to Kragen the other day it was time to change the oil in my 99 Yukon. I have always used the grey Fram Tough Guard filter and Valvoline semi-synthetic Max Life for the last 60k or so. Kragen was out of the Fram so I tried the K&N. The K&N was twice as much, but appeared to be much sturdier and nicer built. So I fired up the truck took it for a spin and I gained 7-12psi across the board. From idle to hwy speed pressure was much improved and seemed to rise faster with rpm increase. In the morning or on a cold start I have been hearing what sounds to be a lifter or loose rocker sound and that is gone now.
I never had an issue with the $7 Fram but K&N for the win in all the vehicles and toys from now on.