i have wondered about this too. My local Pepboys and stuff has a ton of k&n'*, and even a regular filter for my 93 listed, but they dont have it in stock.

I had a drop in for a while. The exhaust note changed a little, MPG went up slightly, and I "felt" a little bit more power. I felt a much bigger increase when I make a custom intake.

dont waste the money on a drop in, do the Rice pipe

We've had a drop in in the SSEi since the week we bought it (brand new). I don't know how much better it flows than stock, however, you never have to replace it, we just clean it every 30k miles or so, and with a gutted airbox it sounds good. I just figure its worth the price if you plan on keeping the car because it pays for itself due to you not having to replace the air filter all the time. Having 137k on the SSEi right now, its pretty much paid for itself.

Shawn

If you read the air filter study on "Bobistheoilguy", you will never use a K&N again. They do flow better at very high revs but they do not filter very well. The test shows they let in way to much sillicon (sand). I took mine out. You can have it if you want it--I need my car to last. By-the-way, the best over all filter was the good old AC Delco.

http://home.usadatanet.net/~jbplock/ISO5011/SPICER.htm This is the link to the air filter study.

I tend not to believe a study on some random persons website. Maybe it is true, however unless you drive down a beach or something I don't see it being a problem. Usually if you get more air flow it makes sense that you would get worse filtration however, so I can easily see it being true... If you change your oil regularly then the difference in dirt allowed in the engine won't really matter because it will end up in the oil (as that is one of the functions of oil, to clean) anyways. My mom has had hers in for 137k miles and her engine internally is very clean, it runs top notch, and the oil is only changed about every 6k miles as it is mostly highway miles. Actually, we have K&N filters on every single car in my sig and have had no problems at all.

Shawn

no offense, but that site is bias. I have seen it many times.