Ive got the 2.3mm Black. This rubber is amazing. Try serving a backspin serve with this tacky one. Ive won many points with that and the sidespin-topspin forehand serve. For the opponent to topspin it is quite difficult. The best part is when you give a float instead of the spin serve, it sets up a smash in a 3-point attack, for which I flip to the red driving rubber, as the neos smashs and loops are not good enough to end the point. The other con is reacts a lot when receiving spinny serves. I would try a red max with a long pips black once, with active flipping. This is a special rubber meant for speciality strokes.