No, I actually brought a mountain bike with me when I moved to San Francisco this summer. It was a pain in the ass so I bought a road bike.
Riding on the sidewalk is incredibly dangerous and stupid. Despite being obnoxious about bike paths and such, the vehicular cyclists are right about a lot of things.
I do like my upright handlebars. More wind resistance but very comfortable. You can get these for a road bike. Though if riding a road bike with standard handlebars gives you constant pain you're probably doing something wrong. The distance between handlebars and seat, or the angle the seat, may be incorrectly adjusted for your body size. (Edit: So I guess my bike, which I bought used so I don't know as much as I should about it, might not be quite technically a road bike. The tall stem seems to be the only really non-road-bike-like feature though. And I certainly appreciate that it weighs about half what my mountain bike did.)
I don't want a heavier bike for more exercise. I want to get places quickly and comfortably and not arrive smelly or sweaty.
On ChrisHallquist's post extolling the virtues of money, the top comment is Eliezer pointing out the lack of concrete examples. Can anyone think of any? This is not just hypothetical: if I think your suggestion is good, I will try it (and report back on how it went)
I care about health, improving personal skills (particularly: programming, writing, people skills), gaining respect (particularly at work), and entertainment (these days: primarily books and computer games). If you think I should care about something else, feel free to suggest it.
I am early-twenties programmer living in San Francisco. In the interest of getting advice useful to more than one person, I'll omit further personal details.
Budget: $50/day
If your idea requires significant ongoing time commitment, that is a major negative.