IMO K&N filters aren't worth what you pay for them. I have never used a Mobil1 filter, but if they are as expensive as the K&N they better do a much better job than the K&N do. I don't know if the Wicks high end filter is good for synthetic, but I have heard nothing but good things about them. I didn't run mine long enough before tearing my engine down to form a good opinion.