Have not used Future, but I just finished re-applying Penetrol to the topsides, slick and non-skid. Put it on last year about this time and it really looks great. It is not slippery and seals the gel coat so you don't go home with white knees. Saw an article in Good Old Boat (I think) which explained the process and I gave it a try. It dosen't look as good as a good wax job but there is no buffing. This year I finished off the smooth surfaces with some Woody Wax and it gave me a little more depth to the shine.
If you are interested and can't find the article I can give you the instructions. Also don't get the Penetrol at West. The stuff at Lowe's and Home Depot is the same formula.
Ray Rhode
S/V Journey
E35-III, #189
