I've used 15 and 30 min. epoxy exclusively until I found out about Hysol. BUT, I always mixed in some glass fibers which at least doubles the strength.

I quit using the mixing nozzles with the Hysol . . . besides a questionable mix, they are expensive, can only be used once, and they waste a considerable amount of the Hysol.I now do all my mixing and application by hand.