Actually, as of writing this post, she now has 25 hours on XCom 2. Apparantly she's binge playing it. I guess that's what happens when you finally get a computer that can actually run some of those games you bought.
Speaking of that, by way of comparison she's only spent slightly over 6 combined hours playing 3 different VR games on the Vive. Now she MAY have been playing games on the Rift that aren't from Steam, but based on the XCom 2 playtime, I'm guessing she hasn't. So, great use of that VR ready PC so far...