As far as epoxy goes, West is great stuff, but it is expensive and most of their products are 5:1 ratio which is easy to screw up (seems simple until you are in the middle of a repair and realize you have to quickly mix up another batch before the first kicks). I prefer the 2:1 ratio epoxies like System Three, Progressive, Raka, etc... They are easier to mix and can be found at close to half the cost of West System.
Two words: metered pumps.
i have used upwards of 75 gallons of West epoxy and never had a bad batch. One squirt of this,one squirt of that,stir, done.
It is virtually idiot-proof.
yeah, in smaller quantities it is about 20-30% more expensive, than the other suspects but, at least in my part of Canada, there are five chandleries, two hardware stores and one aircraft supply house that stock West products. Nobody stocks Raka, Mas, System three, etc. They can get it, but it's gonna take 5 days to a week. I could deal directly with the source, but the price isn't significantly cheaper and i have to pay for shipping. meanwhile, whatever i am working on has to gather dust. If i run out of West 205 during a project, i can get more before the current coat kicks.
Once you start buying the stuff in gallon-plus quantities, the cost difference between West and most competitors virtually disappears, especially when you start adding in shipping...
...and i kinda like dealing with the guys who do the R&D and have built the boats. kinda nice to know i am dealing with a company that has some skin in the game, rather than just some guy with a crappy website whose whole marketing strategy is simply being cheap.