E90 Fleet wrote in part, "Now who is going to go and test the E90's MAF to see if it likes K&N type filters or not ???"
I will not do so. I see no advantage in replacing the treated, pleated paper filter with 1940s technology on a street engine. When I first started noticing the return of oil wetted filters, the pitch from the marketers was, as I recall, that they would save money since they could be cleaned and re-oiled. More recently, the pitch is that they pass more air.