Positive feedback can be explained, because 99% of the buyers are novices. They install it, and "imagine" their car is faster. It's just like when someone takes a stock car and puts on an intake...they automatically "think" the car is faster, because they can "feel" it. When we all know that an intake alone will not make your car faster...let alone so much faster that you can actually feel it. But people still insist that they are faster.
I would imagine that is the case with most of these buyers, they buy it, slap it on, then feel the extra power.
With that said, the IAT mod WILL WORK...and on some vehicles, it can even increase the HP a pretty good amount on SOME vehicles.