I did the Marin Century!! My first century (it was actually 106 miles, plus the 1 mile and terrible but short uphill driveway back to the hotel, ha ha) and I did it in about 9 hours, including an hour of stops!
View from the top of Marshall Wall: (edit: can't get it to work. Here's the link)
http://www.flickr.com/photos/83876661@N00/6020016244/