Halo 5: Guardians sells more than $400 million (games and hardware)

[Insidb]

Here's some quick math, to give this debate an air of reasonability:

Destiny made $325 million in week 1, by selling 2.43 million units (according to VGC).
Halo 5 made $400 million in week 1, by selling a maximum of 1.23X as many or 2.99 million units.

If you believe VGC's Destiny sales estimates, then we have a benchmark (not just random guesstimating and sniping).