Things aren't substantially different in most "bigger" towns in my experience (I've lived in Boston, NYC, SF Bay Area, LA, DC and San Diego). If anything "smaller" places seem to have a better chance of actually having more options since they are more likely to allow for grand experiments or newly built municipal-managed networks. Of course, YMMV greatly depending upon exactly which small town.
I currently live in San Diego and my situation is mostly the same as yours. My cable option (Time Warner) peaks out at a higher speed, but the only other option is DSL at exactly the same rates you mention (6/0.5). And since the cable option is the only viable truly broadband option the customer service and uptime on it is pretty abysmal because with an essentially captive audience why bother making it better?