20 weight is a pretty stable oil, it likely wont shear, but I worry about using 20 weight oil in general. I wonder how many of those cam fails are happening on the 5w30 crowd. And something to consider that many people are talking about is adding a qrt or two of heavier oil just for a little more protection, or looking at a top tier 0w30. I know with much confidence Amsoil EA filters and Royal Purple filters will outlast any oci. Anything else, you guys need to do the work on, my guess would be wix xp would be right there as well, for some reason I think Fram Ultra is a question mark, just because it starts so stiff. It may even outlast a RP filter, but I just don't know, someone should cut it open at a 2 year OCI like I did with the RP filter, that will be a great benefit to the thread whoever does it.