I just took her out for a 14-mile ride to a suburban fabric store and back. Total time in motion was an hour and 45 minutes. I got about as much cardio and leg exercise as I would have in 45 minutes on my regular bike, but I couldn't have gone that far</em on my regular bike. So Gudrun is delivering more than twice the "miles per gallon," so to speak. Plus? So much fun to pass young, fit men in the bike lane.