I switch it up.

On days I'm in a hurry, or otherwise wanting speed, I'll take the roads. 8.5 miles with no hills.

Otherwise, its worth it for me to drop down a hill, take either the 10 or 11 mile MUP ride (two path options), and head up another hill to get to work. No one calls me a *Fa*got* on the MUP or right hooks me, and being by a river, its more than worth the hills and extra distance.