Mostly, I've been biking around Boston and Brookline, but tonight I went to a meeting in Belmont. According to Google Maps, it was 7.3 miles each way. I'd figured it might take me an hour, given traffic, to get there, but it only took 45 minutes. On the way home, with no traffic and a big downhill on Belmont Road, it only took me 35 minutes. Both were much faster than it would have taken me by T.
I'm very glad that I bought a new high-powered front light yesterday ($45), because the way was pretty dark, and Belmont Road and Mt. Auburn have some pretty gnarly potholes. It also helped a lot on the Charles River bike path, which is pretty dark and narrow. (I sure do wish they'd sink some money into upgrading it. It could/should be a brilliant bike/pedestrian path, but it's got a long way to go.)
This was a good chance to check out my range, and ( think 7 or 8 miles one-way is very do-able for events. The weather was great, which made for an especially pleasant ride.