Well, for twisty, the Taconite is your best bet.
For straight aways, the Arrowhead and Bearskin. But be careful on them, some po po have been spotted on them recently.
Personally, I like the Taconite, it runs from Grand Rapids through Tower, and all the way up to Ely. Turns, straight stretches (although nothing like the two above) swamps, hills, forests, just about everything. It gets beaten up in the trees every weekend, but they groom it and its back to near perfection every time.