They're all the same. Loads of noise, no gains until 5000rpm, questionable MAF scaling. Take your pick.
Just MY experience. I have a BWA engine Passat, it has a stage 1 APR map, goes alright. Got given an intake, it made a big difference, right from low revs, and the noise is just what the car needed.
On a full tank of super unleaded it did 37.8mpg cruising at 70ish. Win win all round for me.
I got the intake off my sons MK5 as he has put it up for sale, he said the golf feels flat now with the standard airbox back on.