Google Play Games Services - Realtime Multiplayer in Unity

Hi guyz ))

Yesterday I downloaded a freakingly amazing game called Biotix: Phage Genesis I played it for hours and although I'm not very good at it it got me from the very first game!

Right now I'm about to create a game on my own and really wanted to be with GPG Services plugin with the Realtime Multiplayer that it says it provides.

1) Does anyone know whether this game's multiplayer is made with GPG Services realtime multiplayer? Is it with the plugin that I pointed? It looks like it is made with it but I can't be sure.

2) Can anyone tell me if it's developed enough(the plugin's multiplayer option) so that I start learning it and to use it in my future games? I started learning UNET but I cannot be sure what the pricing is going to be in the future so I prefer at least for now to make the game with the GPG plugin.

3) Has anyone made any realtime multiplayer games with it? (it == the GPG plugin)

4) Or does anyone know any realtime multiplayer games that are created with it?