I used laun (door skin) for my early boat efforts and it was fine, but later I ran into sheets of the same stuff that were awful. I painted one and the outer veneer bubbled due to missing glue, one had the outer veneer hanging in shreds (in the store it was stacked with the only good side showing), another showed bumps when I flexed it due to core voids: all unusable.

I have found it possible to obtain Okoume marine ply below the market price (even higher here in Canada).The last time my supplied had a stack of sheets spoiled by snow melt in his storage shed, I got 10 sheets for 1/2 price, it just had slight water stains in the corners but good stuff. I can cut the painted bits from the edges and reserve the middle of the sheets for parts to be varnished.

But I'm a traitor to the cause: my next boat is a sailboat.