Any bros have this installed? Basically the GNG is just a canister, it works by storing a fixed volume of air when the engine is started. When the throttle is released, the air is fed into the engine, which "fools" it that the throttle is not fully released. Hence, upon re-acceleration, the engine can response faster.
My colleague has installed recently, basically the installer remove the air-pipe between the air-intake manifold and the master brake pump, and installs the GNG in the way. Typically it's about 300cc GNG for 1.5l car, and bigger volumes for bigger engines. The size of GNG can be selected to suit different driving needs. The market price is about $140.
I have called one of the installers, and he's kind enough to give a 1-week trial for the product, and a small discount. Makes it even more tempting , but I'm still considering...