Without a doubt I reccomend using an epoxy that is at least as thin as System 3's "clear coat." I admittedly have not tried mas or west but I did use raka and it's not thin enough for me. I like not having to fight the epoxy to get it to wet out the cloth. It's a bit spendy but I only use it for the first coat and then apply regular fast setting system 3 over that. Whichever epoxy you decide to go with make certain that you apply it carefully, avoid runs and sags, strive for smooth even coats. Doing this will make a stronger better looking canoe because you will not sand into the cloth trying to erase the sags. The 10 extra minutes spent assuring a run/sag free, smooth epoxy coat will save hours of sanding prior to varnishing. It takes me about half an hour to prep an epoxied hull (canoe) for varnishing and I use less than a dozen sanding disks.... about 20 fewer than a blotchy epoxy job will use. Blush has never been an issue for me. I let my first coat cure for a couple of days and then each subsequent coat of epoxy is applied after the other is just about set up. The little bit of blush that I have encountered after the last coat has fully cured is removed easily enough with a bit of vinegar. Doug Keaster, BPCC