The boats I've built with meranti (I'm just a hobbyist, not a pro boatbuilder) were all stitch and glue plywood hulls. They were all designed to be sheathed in fiberglass inside and out with several overlapping layers of glass at the critical stress areas.
Many of the non-hull parts in the cabin/pilothouse skiff I'm building now are 2 step MDO. This plywood is basically doug fir with ext glue, no voids that I've seen yet, and a paper covering on both sides. I'm using it for bulkheads where I tape the edges to the hull, lockers, bunk tops etc. It saves a lot of time finishing it compared to marine fir, but I still coat it with a couple coats of epoxy to seal it.