I just use Wix filters.. my daily drivers, they might get changed once a year. usually I forget they have them until the MPG starts to tank, and I figure it should be replaced, and it usually does ( I kno this is bad, but my Daily drivers arn't that nice )... any filter is going to do the same thing.. so I could buy a $5 filter and replace every 6 months, or buy a $50 filter and replace never, but still need service interval, every 6 months + the cost of the maintinance supplies.... I go the cheap route because I don't keep vehicles long... but I'v also had to clean the oil filmed MAF's on K&N filtered engines