Composition and production are usually related, but not necessarily the same thing. Production can be accomplished using pre-existing beats and music loops; which would mean the Content ID system might match something similar but not completely the same as your music. If the accused YouTuber doesn't dispute, you might earn money on a piece you have no rights-entitlement in. This is why I don't agree with the Content ID system as it exists today. Twice this week, I had to dispute claims where the matched music piece bore no resemblance to my own.
I just took a close look at Beatstars also; it is much like Tunecore or Rumblefish, except for the fact it seems to be a one-stop collaboration community as well as a distribution/rights managing outlet. I cannot use such a service; one Content ID against my own distributed works would invalidate my contract with Shockwave Sound.
Unlike youself, I compose/produce soundscapes for Royalty-Free Distribution.