Keep in mind that even the West and System 3 epoxies have a shelf life. I had some left over from building a kayak and decided to use some after it had sat in my unheated/uncooled garage for a couple years. I mixed it very carefully but it just wouldn't set up right. I think with any adhesive it's not a good idea to buy more than you think you'll use in a year.
My favorite adhesive for knife scales or close-fitting parts is Loctite 324 and the 7075 spray activator but it too has a limited shelf life and it's expensive.
I use the Devcon 2-ton for hidden tangs and always have good luck with it. I read some big test of various epoxies on another forum and Brownell's Acraglas seemed to do the best in their various tests. My local hardware carries the Devcon though so I keep picking that up when I need some.
Here's a link to the big adhesive test but you have to be a member of that forum to read it. It's 19 pages in all and the summary of opinions/findings is on page 16. They really had good results from Gorilla and Sumo glue for general purpose stuff too.
Devcon epoxies got an F
West epoxy got a D
Acraglas got an A
Golf Shafting epoxy from Golfsmith got an A and it's cheaper than Acraglas.
http://www.knifenetwork.com/forum/showthread.php?t=27463&page=16&highlight=epoxy+test