Sorry, EMD...
... but your statement is a bunch of BS. K&N oil filters are not even made by K&N, I believe they are a Champion filter - they are also the same as Mobil 1 filters, and have filtration ratings similar to all other common filters. They are perfectly fine for Cummins use; the materials of construction and quality is much better than Fram, for example. The best feature is the 1" nut on the bottom, which makes it easy to get off with auto trans. and A/C, as space is a cramped, and especially if the filter is very tight.