I ran the K&N cotton filter for the first 100,000 miles. I did not really enjoy cleaning it every 20,000 miles. While waiting for the cleaning solvent to dry, I put the stock paper ACDelco filter back in. Then the van did not run right. I had to disconnect the battery and then watch it stall and sputter while it relearned how to meter fuel. Repeat the same annoying thing two days later when putting the cleaned and re-oiled K&N filter back in. After 100,000 miles I switched to the Amsoil EA filter. It uses nano-fiber technology, the same as their oil filters. Now I just blow the dirt out with low pressure air and put it right back in. Easy!