I have 97 and 98 Camrys under my care. Both have one of the 4 cyl engines that are sludge prone. Both are over 200k total miles and I'm pretty sure neither has any sludge at this point. I was planning to go 10k ocis on them using M1 and a Mobil 1 Extended Performance filter. After gathering more info, it seems that an oci more in the 5-6K range makes more sense. The Mobil 1 Extended Performance filter is overkill for that oci so I'm thinking of a filter that is more in the $6 range. Two of the available choices would be the Pureone or the Toyota OEM. Which would be a better choice? Or does it even matter in this case?