I do the same thing as Dave for the same reasons. I build with 3mm luaun, by sealing with epoxy the panels become a bit stiffer but that actually works to an advantage.

I use a 3 oz VERY tight weave cloth [32 strands/inch]which is difficult to wet out and does not drape easily. I will often apply a layer of fiberglass to the inside of the panels before stitching them together - but I make a point of stitching and filleting as soon as the epoxy is set enough. Drilling holes through the glass is hard on the drill bits [dulls them quickly] but I get around this by using carbide bits [these are used for drilling Printed Circuit Boards and are available from Lee Valley Tools].

I used this construction on my current kayak - a Chesapeake 17 LT and with out paint/varnish and the cockpit rim it weighs 35 pounds.

Hank