2016 Mazda 6 touring 6MT
Well designed, nice fit. I only put it on a week ago but the initial impression is good. I've had similar k&n products on previous cars with no problems for 20k miles so I had no reservations getting this one. When I took out the enormous, very restrictive looking, standard air box I was very confident a noticeable hp gain would not be difficult to get. The car now has that little extra power and sportier sound that really make it a better drive.
Excellent purchase. My only regret is that I didn't install this sooner. For the price I don't think there's even a question if this is worth the money. The only thing I wish that would have been much more useful would have been if they attached color pictures with higher resolution. Even K&N's website had the same manual in PDF form with color in some parts, but all images were black and white, which made some parts of installation a little trickier to understand.
I have used K&N filters on all my vehicle for the past 15+ years but this is the first CAI system I've installed. It is very easy to install for anyone who does simple maintenance. You can notice the improved acceleration, it works. I am pleasantly surprised that it DOES increase the mileage in my Mazda 6 by a couple MPG. There is a strange 'growl' at low rpms but it shouldn't be so bad that you would want to 'unload it' as a read one reviewer say. Using the Sport mode of the transmission makes that go away. Very happy with the product.