Hal Roth (How to Sail Around the World) uses one part poly and coarse sand for the decks on his yachts. If I remember: wet coat, sprinkle on sand with sugar shaker, two more coats on top.

If the boat is going to get used a lot, cruised, the arguement is safe sure footing and the ability to repair the surface easily. No nonsense.

If you're going cruising. this book has a huge helping of great practical tips.

I don't want to be convinced that I need a 36 grit surface on the deck!
But, we don't have that much deck. When I think of having to go forward on a heaving boat streaming with green water on a dark and stormy night.....