I bought some gearbox treatment in October as a last resort, it is the smoothest and easy shifting! I also have a mk2 golf gti 120K and the fuelling is problematic, the engine returns to idle like it has an air leak, acceleration is not the best,a little fuzzy, have been trying redex injector cleaner for over a year, it helps but... Last weekend I put this stuff in the tank, after filling (contrary to directions) I did a ten minute trip. Today I took the car out and already the results are ridiculous! It revs cleanly with no fluffing on the over run and the pick up/acceleration is better than in all the five years I've owned the car, interested to see how good it gets