Welcome to the world of cycling! I have to agree with the others. A single speed will find you discouraged soon and you want to be able to enjoy your commute. Bikes differ SO much in handling and feel. I understand why you want to buy online but trying a minimum of two different bikes really is the way to go. For instance, I was certain after doing some research, that a certain bike would be just what I needed but when I sat on it it was completely wrong. It's definately worth a trip to the bike store and in Rochester there are many good ones. If you buy on Craigslist ask to try the bike, even briefly. Happy cycling!