My commute's a little over 9 miles each way, probably 5 miles suburban streets, 2 miles MUPs, 1 mile rural road, and 1 mile downtown. It's Sacramento so it's flat as a pancake and winters are easy (summer afternoons can be a drag tho).

With all the stoplights/stop-signs (and my weak engine), it takes me 45-55 minutes. That's a pretty good distance for me. I wouldn't mind about 3 miles shorter, but 9 is okay. I probably wouldn't do it if it were over 15 miles.

Partly for traffic reasons and partly for day care reasons I go in early (6:30 arrival) and leave early (3:00 leave). That means I ride in the dark every morning. That's okay too, in my book it's safer than the higher traffic at rush hour.