I have used numerous brands of air filters during my 37 yrs of riding MX and Offroad and IMO nothing does a better job than the Twin AIr. They dual layer foam when combined with proper foam filter oiling does a much better job of preventing dirt, dust and sand from getting into the engine than any single layer filter. It is as easy if not easier to clean than the two piece filters. The glued seams and foam hold up well to multiple cleanings. This is the best insurance you can buy for a long lasting, clean carb and top end.