I just installed a K&N 63 series on my 07 Rallye. I paid $187.00 shipped to my door from autoanything.com, about $80.00 dollars cheaper than I could find anywhere else. Suprisigly I could feel an increase in power and no longer seem to have that low rpm 2nd gear bog. It took about 45 minutes to install it and was fairly easy with illustrated step by step instructions. I was weary at first with the kit because the intake tube is made of a hard heat resistant plastic and not aluminum or steel, but it really helps with the noise level. You can accelerate nominaly with no real noticeable increase in noise, until you get on the gas and then the thing just screams. I had my friend drive by me twice in it while I was on the side of the road. First time accelerating as usual, nothing aggressive, sounded like a normal car. 2nd time around he really got up on the gas and holy crap it sounded like some race car out of hell. It had a turbo sounding mechanical wine and a really aggressive WOOSH when he shifted, it was awesome, it sounded really mean. After the the first week driving mellow again I did see an increase in fuel economy, I will update with the exact numbers because I still need a better base line as of yet. All round a good plus. By the way, anyone put a stage 1-3 turbo on their jeep yet? Im intrested in a single stage 240hp, anything beyond that seems futile.... no traction. Anyone have any good advice?