I've seen them for diesel trucks before but I guess they sell them for cars and motorcycles too. The truck filters were in the $200-$400 range so that falls in line with K&Ns filter. Personally, I'm so off the K&N bandwagon that I doubt I'll ever buy another one of their OEM replacement air filters again and definitely won't be partaking in their permanent / reusable oil filters. Like they say, I don't know if they filter better or worse...or flow air better, but they stay out of the landfill longer.
i think it would only be worthwhile on a new vehicle if one were concerned about overall costs of filters...but i just wonder how well this thing filters compared to the traditional paper element and how it would hold up in the long term.