I don't know which filter is scientifically proven to be best. I just use the K&N because they work well, with a reputation for quality. But mainly I like the welded on nut for easy removal!
Now to sit back and watch!
OEM for me as long as my warranty is still active, and probably beyond that because they are easy to get and there is no little voice in the back of my head asking, "is this filter going to be ok?". I do agree that the price spread is not big enought to be a factor. Even for my Ducati ($17 ) i'll stick with OEM.
K&N for me, it's built lilke a tank and it's easy to get off with the welded on nut.
I am shocked by the amount of chatter that I see here for the Walmart Supertech filters. Call me crazy but I would never put a generic filter on my bike.
I just looked at the K&N, KN-303 that I have sitting here. It's made in Thailand.
So are my Michelin tires, does that make them any more inferior than the French made Michelins. We now have tires and oil [filters] in the same thread, just waiting on KiPass to enter the discussion............
I guess we could do a simple, non-scientific experiment.... I installed one of those magnetic oil plugs on the last oil change, AND used a Walmart ST7317 (*GASP*) filter.
I'll take a look at how much dung gets collected by the magnet. Maybe I'll take a clean paper towel and wipe the plug and save the paper towel. Then I'll use a K&N-303 and see how much chit gets collected after the same amount of miles. This may only indicate how much debris gets through the filter and not really speak to how well the oil gets filtered...hell, that may be one in the same- it's an idea anyway-