Depends which transit option I take. I voted somewhat slower because if I take Metra, it can be as fast as 40 minutes door-to-door for an express train, including walking to and from the stations at each end, versus 1 hour for the 16 mile bike ride. If I were to take the CTA, even on the express train, on the other hand, it takes more than an hour to get downtown. And I regularly pass CTA buses during my bike commutes.