I would extend that to most of the Reds we can grow out here in the Midwest, Norton, Chambourcin, St. Vincent, Frotenac and Marquette come to mind. But that just goes with making grapes from hybrid grapes, although Norton might not be hybrid, I suppose.
My hardest has been a fruit wine, two come to mind, Pear and Peach, both for the same reason, hard to get the durn things to clear.
Hands down, watermelon. I hadn't been making wine very long, think I went to slow trying to get it to ferment. Stuff spoiled before it got going good. Anyway, havn't tried it since. Maybe someday, think I could make it work now without any problems. Arne.