I built a S & G with doorskins (1/8 Luan ply - $7 4 x 8 in US) As one person said: If you're going to paint the hull, why not. Maybe one sheet of Okume for the deck if that's what you want. There was a thread a while back and a lot of S & G builders are even glassing the inside (which I didn't) which would make for an abnormally strong ply.

I have a strip deck and I'm painting the hull. The Okume is superior - no doubt about it. If you get 1/8 ply, get an extra sheet because there will be an occassional void in the ply. Run over it with a drop light and it will show up usually as a small light area.

Actually, for the price I paid, I couldn't believe the overall quality and the quality of the good side veneer.

Now that the bulkheads are in and layer of 6 oz cloth on the outside plus the taping on the inside, the hull is like iron.