On the subject of: "is the Xbox One selling better than the Xbox 360 did?", I made the following chart:
So, yes the Xbox One is still around 800k units ahead of the 360 launch aligned. But by breaking it into periods you can see that the One had a fantastic launch and has since slowed down a bit relative to the 360.
I wonder how much of those 360 were consoles sold because of RRoD.