Underground or Mainstream music?

[Bridge]

Mainstream, I guess. The type of genres I listen to usually do not have the phenomenon of mainstream vs underground, at least not in a manner as pronounced as in popular genres, and whatever is most famous is as a general rule of thumb the "best". I don't shun music that is unknown however and I don't use ad populum arguments to suggest that that which is best known is the best, so my answer is a sort of up-and-down "neither" in slight favor of mainstream.