About 10,000 minutes.

Spotify started out pretty damn cheap, and had almost everything I wanted. The selection has gone up, but so has the cost. Compared to the thousands of dollars I used to spend on music every year though, Spotify still costs, comparably, next to nothing.

As far as why Spotify vs some of the other services...at this point, it's that it knows me and my tastes, and it would take years for another service to be able to form the same type of suggestions/playlists that Spotify does, AND the fact that it has XBOX integration, so I can have my own music playing in non-narrative/audio-dependent games, but that's a huge #2, behind the algorithm thing.