I like the new text messaging and lock screen features, but honestly I found it a little underwhelming. Apple advertised it as "the biggest IPhone update ever," but there wasn't anything new that just completely changed how the phone works. I also find unlocking the phone to be a pain now, as you have to actually click the home button instead of putting your finger there. Not a big deal, but I often find myself unlocking my phone as I take it out of my pocket, and I don't always remember to click the home button.
I can't say anything about Apple Music, as I just use Spotify.