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On tracking, I would say bluntly that it sucks. I think Mad River should reclassify the boat as a river boat, not touring. But, like someone said to me, "the various manufacturers seem to take their mentality into their product line". Wenonah seems to take their racing background into their product line and Mad River with their whitewater background seem to not be able to get away from the excessive rocker and other river emphasis.
The boat is a delight on the Pennsylvania Grand Canyon but it's a pain on the Finger Lakes and Adirondacks. We have a cheap junk Pelican (formerly Coleman) and even that thing tracks better on lakes than the Horizon 15! So we keep the Horizon 15 for the river runs and for guests who want to go with us to the Adirondacks canoe-camping. Just remember: what Mad River calls "touring" is not what I think most people think.