> What are advantages and disadvantages of plywood bulkheads against foam
> ones?

> plywood - pro:quick and easy,strong platform for mounting things,quick and easy structural support for back of coaming/deck. More room in compartments. fillet is obviously sealed or not.
> con: if it isn't cut well there is a lot of messy fillet to deal with, the whole stress riser issue can be a good conversational topic, probably any impact that is that large might bring other problems. Tired of making ugly epoxy fillets foam-pro: It's fun to cut and size and install. The boat absolutely won't sink ,although if one is at that situation then there might be other concerns. You won't stay up nights wondering about stress risers. Makes the boat look more "production". I installed foam bulkheads on my North Bay just because I didn't want 6mm at right angles to 3mm.

con: if you didn't cut the foam right too much adhesive/sealant is used. 3M 5200 is absolutely heinous messy stuff. This is pro or con but for kits with integral bulkheads as back deck beam you then need to make one in order to install the deck.