Caribou and it isn't even close.
Funny. My family had withdrawals going back to beef and pork after we ran out of caribou last time. It's probably the best meat I've ever had.
I've tried to eat hoary marmot a couple times. It reeks of marmot BO and tastes just as bad as it smells. I was told they have scent glands that contaminate the meat if you're not careful, but not matter how we handled them, we all got the same results. Porcupine isn't much better.
Jackrabbit from N. NV isn't too bad. I've stewed it and fried it. I'd prefer beef instead by a longshot, but it was edible. I haven't tried it with the method from Rinella yet.