I used East System from Noah's, and it worked great for me. It was a bit thin, though, which was great for glassing but I had to add a lot of dry material when I wanted to thicken it up. I've read that West System and System Three are comparable. I've also read there can be problems using different kinds of epoxies, because of different thinners and hardening agents. I don't know if that's a theoretical possibility or a real concern. As for Noah's advice, I wouldn't put too much faith in it. They seem to make it up as they go along. Visit the store twice with the same questions and you'll get two sets of answers, neither necessarily correct. Like being told that wood flour is useless, that a micro-balloon/epoxy mix will dry transparent and that the same mix is just the thing to glue the sheer clamps. All in all, it's an excellent, well stocked store, but I'd listen to the kayak designer before Noah's staff. (I'm sure they're fabulous if you're discussing sail boats.) As for East System, I think they're a Quebec company, so your Franglais keyboard may be useful if you decide to contact them. See you on the lake.