I would absolutely go for the 117W over the 117. Det 117W is far better low end. And it will carry the 8,6 much better. It will go superbly with the 7,8 also.
I often use my 7,8 on my IS127 with either 46 or 48 fin in 12 m/s. Pulling the mast base a couple of cm back from centre and the board dances gracefully over the chop. I would guess the 117W will do the same.