I enjoy Google Play Music and use it daily (the paid version). I prefer it over Spotify/Rdio/Beats because it works better with Google Now voice actions, and I can run it well on every device I care to.
My remaining problem with it is their device limit. You can have 10 total devices, but you can deauthorize only 4 per year. This sounds like a lot but if you switch phones often or flash new ROMs you can use it up pretty quickly. In addition, if you upload music to the service the computer you use counts as a device. Once you're at your limit there's little you can do and you have no information on when you'll get a device deauthorization "credit" again. I had to call Google to get a one-time reset of my authorizations but it would be nice if they could modernize this some; such as by only using an authorization if you download music to the device for offline listening.
My bigger issue that two clients cannot be listening to music at the same time, even if you're a paying member.
I'll often forget to stop streaming the music at work and start listening to it on the bus on the way home. My workstation at work then fights for control of the service with my phone and every other song drops out with "another device is using the service".
And the really stupid thing happens if you try and play a youtube video while listening to music. It freaks out about playing a youtube video at the same time.
Whichever genius at Google came up with that one deserves a rapid promotion into the tiers of bureaucracy.
Weird I've done that before but I didn't even know until i went back to the other device. It's only happened twice that I left it running on a radio station though.
As a workaround i've setup Chrome Remote Desktop at any PC i use, so I can easily connect to them without much network hassle and turn off stuff like Google Music.
Seems like a pop-up implementing this would be ideal, since it's most often accidental: "Hey, this is still running on another device, and you're only allowed 1 device at a time - do you want me to remotely kill the other device's Google Music session?"
After all, most of the time it's not another human using both sessions at once.
My remaining problem with it is their device limit. You can have 10 total devices, but you can deauthorize only 4 per year. This sounds like a lot but if you switch phones often or flash new ROMs you can use it up pretty quickly. In addition, if you upload music to the service the computer you use counts as a device. Once you're at your limit there's little you can do and you have no information on when you'll get a device deauthorization "credit" again. I had to call Google to get a one-time reset of my authorizations but it would be nice if they could modernize this some; such as by only using an authorization if you download music to the device for offline listening.