Loud tweetering noise
The install took about 2 hours (I don't come from an automotive background) wasn't too terribly difficult thanks to a YouTube video I found which walked me through the install. There are some noticeable gains in HP but the biggest downfall to this product with the loud & obnoxious tweetering/reverb sound the intake makes when you are accelerating hard over 3/3500 rpm's. I'm likely going to take my car to a performance shop to see if there is anything they can do to correct this sound.
Well made product
Installation instructions were easy to follow. Had to do some minor modifications to holes for screws. One would not line up correctly. Overall well made and easy to put in. Engine breathes better. Installed with magnaflow exhaust on 07 Audi A4. Runs great sounds awesome and mileage increase was noticeable right away.