It's been said that the OEM subaru filter is made by framFram works just fine. I have cut them apart, its a oil filter. It has a bypass valve, filter media, and thats about it. I know it uses the black gasket instead of the red, but our filters are downward facing, so that does not matter at all. In racing on big dollar engines they are used almost universally. For some reason people have given them a bad name, but based on what facts? Their single and multi-pass efficiancy is plenty high.