Hello, This topic had been covered & covered, but the page count for the threads is astronomical. Apologies for resurrecting the question. So far, I had been using amsoil and their filters, changing them annually, "normal" commute. I was planning on switching from amsoil oil filter 1/yr changes to wix 2+ oil filters changes per yr because of less costs of wix and switching to a fresh filter more regularly. My goal is to have a well maintained car, but not spend all my free time to maintain it. Could someone suggest / recap if the Wix filters are worth it and if Wix XP filters actually have a decreased efficiency and it's worth sticking with the plain Wix ?. From the other perspective how do wix xp and amoil filters compare, can they handle once / yr changes ?