I have applied the Nowacs to a board and surfed it a few times.
It is about as grippy as wax, maybe better, but maybe not as good as the rough deck grip stuff that I am used to.
It is hard to tell if it is less grippy or just different. It was interesting to find out how much I got used to the very good and consistent grip from the red carpet stuff I have on several boards. I bought half a roll of it for very cheap. It was also interesting to experience how used I am to the 1mm superstretch wetsuit I wear (to keep my skin on) when surfing boards with the red deck grip.
Surfing in board shorts on the Nowacs board, it was disorientating during wipe-outs to not have that little bit of positive buoyancy from the wetsuit. And the Nowacs felt different under my feet when popping up, making me a bit nervous about slipping, but I never actually slipped. The board is also brand new to me, although it is a close copy of my favourite type of board (TSA 8’0’’ McCoy Nugget converted to single fin).
I surfed in shorts for 45min on the Nowacs and got mild skin irritation, I think it would have been very similar on wax, because my skin is not used to it.
I also surfed the board with wetsuit and there is no slipping whatsoever, very good grip, as expected from my preliminary bench tests with various rashies, shorts, wetsuits and booties. This silicone stuff is grippy under any material I have tried out.
The board was also used for more than one hour by an absolute novice surfer in a bikini and caused no significant rash on knees or anywhere else.
Application of the Nowacs to the board was a bit more difficult than other deck grips I have used, because it is very stretchy. The backing is not stretchy, and the force needed to pull it off during application will stretch the silicone enough so that the ends of patches do not line up any more. It was easily fixed by carefully cutting it back with a Stanley knife after sticking it to the board.
The 3M adhesive backing is just as good as it is on all the other applications you might have used it in.
I weighed the backing film that was left over after application of the Nowacs and calculated the weight of the patch on the board as 0.684kg.
I’m very happy with it so far and recommend it for surfboards for which a bit of extra weight does not hurt.