Having just moved the other week, I've bumped my commute up to 22-24 miles depending on route. Currently on the steel fixed gear till I finish the road racer, the computer has rated me pretty consistently at 19mph door to door including stops/slowdowns, accelerations and catching my breath before going inside. There are a bunch of decent hills on the route and each way there are several miles where traffic is backed up for lights that I've gotta carefully thread the needle between the dirt shoulder/woods and car mirrors (most of this route only has a few inches from the white line to curb or dirt, going to suck in winter). Whenever I can safely check my speedo it tends to be around 22-25mph with max speeds at 30+ while spinning out.

Driving has taken nearly the same time, greatly increases the chance of me beating myself senseless on the steering wheel in bumper to bumper traffic, burns nearly 2 gallons of gas and costs ~4 bucks in tolls a day for the privilege.