Yea, there's lots of them going for just a few dollars on eBay and they make up the difference with the shippping cost. I'm pretty sure you don't get the washable filters with the cheap ones, so when you need a replacement filter, it will cost as much as buying a whole new one.
A lot of owners don't like them because they draw in just as much hot air from the engine as cool air from the hole in the wheelwell, and cooler air makes more power. If you don't care about the couple extra HP (like me) then the short air-intake is OK as it draws in more air than the OEM filter and it does sound good, as you stated.
