My dad's response is "if you find classic musics as to be good to your ears, that means that you're matured enough".
I do agree with my dad's statement and even though it might not be 100% true, it does reflect your maturity in a way.
As for the music, those singers and musicians would tend to produce music that reflect their age and maturity. Look at Lady Gaga and Dave Matthews Band.

I would say that I'm not that matured as I do love 3OH!3 but I also love Elvis Presley (Suspicious Mind).

p/s: I'm envious of my friends who are getting married.