I have one. it does what it says it does.

I know of another TSI Octavia owner who has one. He has the same outcome as me.

I find that it doesn't open lower down in the RPM and I get a little flutter.

basically, its fimer spring that can hold higher boost, but still retaining the factory solenoid. unlike some other kits that convert to a vacuum type BOV which IMO is slower to activate/react.