West sure has a loyal and knowledgeable customer base and granted that counts for something but I'll go on record as not being in the group. I used it for one build and wasn't impressed enough to justify the cost. I'm not bashing it - it's good stuff, just not that good.
I'm surprised that Clarkcraft 50/50 gets little or no reference in epoxy discussions these days. I believe it's the oldest brand out there and I have had good results with it. I love the mix ratio, and good support when the guys in the back get around to cleaning their hands and answering the phone. No blush issues and very reasonably priced. The bond is more flexible than most other brands and honestly I don't know the advantages or problems with that but no issues here.
When we (Robin and I) built our yaks we did hers first with Clarkcraft and mine second (I got manners) with the west system. Side by side there is no noticeable difference, one just cost a lot more. With two years and somewhere around 400 miles the boats are showing no difference in wear.
I've also had good results with the US Composite epoxy. There was an issue with clouding in one build that went unresolved and honestly I would have to say chances are good it was related to the Florida humidity more than the product but I just don't know for sure. Tons of good information on the website though.
The most recent product I've used and I'm pretty excited with it is epoxy by Huntsman called Ardelite. Very cost effective and a pleasure to work with. The distributor is close by and they have good prices on supplies too. Here's a link: http://www.carbonfiberglass.com/
Two boats with the Huntsman system from Illstreet and I think I've found a favorite. Hope that helps.
BTW, thanks for posting that link ezwater, very informative.