Roots & Pagelines seem to be the more robust of the themes using Bootstrap. I'm trying to build my own theme from scratch using Bootstrap and whenever I finish that, I might make it public (hopefully before the next presidential election.
I don't quite get why anyone would want to use Twitter Bootstrap. I've never seen a well-coded site that uses the framework. I've had to work with it due to the client having taken it onboard before handing the rest of the work to me... All I can say is, what a waste of time.