My dad and I fished Yale Sunday afternoon. We hooked between 10-15 kokes. Landed about 1/2 of that. All fish were between 8-10 inches; very small. All of the fish that we marked we down to 90 ft., but the fish we caught were near the surface. 3/4 - 1 oz. of lead in front of lake trolls and wedding ring/corn, out 30-35 pulls. We also hooked into several 10 in. trout. Hopefully we'll do better in the next 2-3 months.
From my experience, the kokanee in Merwin are bigger, but they are mostly hatchery raised. Yale fish are native fish, but they are smaller. You'll catch more kokes in Yale, and you won't have to put up with the squafish. Yale kokes are much better eating, too!