Fuel economy went from 19 to 21 on the freeway. Freeway was really the only thing I noticed. But it was definitely from the intake. I never saw 21 before, which was significant because that is what my 2003 5.3 Tahoe would get and I was frustrated only seeing 19ish from this thing(but figured all the extra power was worth it

).
The power gain was very noticeable and it sounds great when you put your foot down.
Like I said before, I can get these things and sell them already modified for you guys that are interested. We were going to build our own, but I never found a source for the MAF flanges...