Just wondering what is meant by deck and surface feedback when referring to knee pucks? Thanx!

harder plastic will tend to "skip & bounce" when initially hitting the pavement. Softer plastic and leather will glide along, but still give you a good impression of surface poracity, gription (grip and traction), and ability to push off the ground at will. THe harder, cheaper plastic won't as easily give you these benefits, especially the ability to push off the ground without sliding back in the seat.

I have used soft plastic, leather and hard plastic. It all comes down to what you prefer. I like the Hard sliders but agree the leather can assit in helping save a frontend push by giving bite.

I have burned through a large number of sliders, have not found one I did not like yet. I prefer to use the tires to measure the level of traction myself. Saving the front can be done while wearing any slider, has more to do with the technique than the style of the slider. I have even went out without any sliders accidentally, did the whole session that way and went as fast as I did with them on. Suprised how fast you could go without touching the knee down.