Let's approach the question from technical viewpoint:
Due to my experiences (over 50 types of rubbers) I suppose that both rubber and sponge are important in the field of accerelation. The fact that the pimples are out or in doesn't matter. There are two possible directions:
1. extra hard sponge with extra hard rubber.
2. everythig is soft.
Let's start from the 1st situation. If you have any Frendship rubber with yellow or blue sponge (even KAWA 2.2 extra hard sponge) your paddle is quiet dead but hard despite the amount of any kind of glue. In this case you cannot use anything else to accerelate the ball than your power. You had better use a piece of wood or baseball paddle.
The second arrangement has also the same problem because the ball sinks into the rubber and sponge to the wood and we arrived to the baseball paddle case again.
I am convinced that the most effective solution is rgarding the speed:
- 2.6 flexible but dense sponge that can accumulate the power of speed glue (sponge of Joola Terminator, Donic Supersonic M/S 40...etc.)
- a piece of rubber with a built in glue effect (Tensor or High Tension)
- Yasaka Super Speed or Bfly Master Chack glue
This is going to be a real destroyer because the above components add extra energy to catapult the ball in addition to your own power. The control is an other cup of tea...
Please, note that recently the "catapult effect" and speed has been shown in the mixed catalogues. You can compare the Frienship to another and vica versa.
The Friendship rubbers have only one advantage: its price.
Everything is relative
