I have it, my mileage improved a bit and feel a bit better response for passing. I would say the best feature is that it is street legal and cost less. I had to ask them to send me the CARB# sticker, 2 days later I got it in the mail.
To me a weak point is the sound, it does not add much of the throaty sound like other systems because the stock air box is maintained and acts like a resonator. You can hear it a bit but not like the systems that feed directly into the throttle. The air is not all outside air because it forms its box with the top being the hood.
Overall I would say if you want more air and want a CARB# and you save some money this is a system you can go with, if you dont care about the CARB and want more sound consider others.