I have also used the Epo-Grip. They have a fast setting and slow setting formula. The fast set gives you about 5 minutes of working time, and the slow set gives you about 45 minutes.

But the slow set takes several hours to really set up, so I only use it on "overnight" gluing items. That said, I really love the stuff. I has the consistancy of Vaseline, so once you smear it into something like a wing joiner pocket, it won't all run down to the bottom of the pocket like regular epoxy will.

I like it best for joining wings and installing Robart Hinge Points