Google Play is the stock music application. I only use it for Google Music which is an excellent service by the way. Everything else I use PlayerPro for which was something around $5.
A spinoff question: How well does music play on the new Droid MAXX? In other words, does it have periodic skips or pauses during playback?
The reason I ask is because I occasionally have this problem on my Razr MAXX HD. Usually happens when RAM is low or I recently had used a lot of apps before starting music player. (I suspect the other apps are causing wakelocks which causes the music to pause.) I can sometimes remedy the problem by Force Closing running and cached apps, but this is annoying.