I've been riding to work most days for almost a year now, first 3 miles each way, now about 3.5, on three-speed bikes.
My first Schwinn Breeze was stolen, replaced by another, and then by a Western Flyer three speed. That bike recently developed serious problems in the rear hub (a Shimano 3-speed IGH from the 1970's), and I am now considering buying a new bike, instead of spending $150 to fix this one.
I joined up because I'm considering spending $500 to $900 on a bike and would like some advice. For now I'm interested in the Torker t-530 or Graduate, the Novara Transfer, or the Breezer Uptown. I like internal gear hubs rather than derailers, due to the easy downshifting at red lights and lack of grease, and want to be able to ride in the rain and at night without worries. I like riding slow enough to work to avoid getting sweating; changing clothes is too much trouble. But I do tend to go faster on the way home to get more exercise.
I did ride an old 1980's 10 speed as a freshman in college. After that was stolen, I bought a newer mountain bike with indexed shifting, which was much better, but I really should have had a rack and fenders and lights, looking back on it.
I don't have a great deal of bike mechanical knowledge, but I see no problem in spending my money at local bike shops for repairs. It sure beats paying $500 every time my car broke down!