I just fitted my new MAS adaptor for my Quikshift Cone - what a difference. I had a makeshit metal adabptor which didn't really fit the GS MAS properly (same as GR) - it obscured some of the air inlet and I reckon was leaking..... I cannot believe the improvement, the car is much nicer to drive with more instant throttle response.
Once again I've learned the hard way that its better to get parts that fit properly instead of trying to "make" something fit.