I think the reason they're hesitant is because they're not sure if they can really compete with Spotify, Rdio, Google Music and YouTube!

Even if someone is able to stream one song they couldn't find anywhere else, 5000k artists isn't going to satisfy them for long.

Go in at 12 months if you think it's worth it, but don't do month to month on this. Personally, I would punch a sales person at my company if they sold this client SEO.