I wouldn't put a cent worth of money on their analysis. For all we know VGC is slightly more accurate and even it is completely unreliable for Xbox since there isn't much formal data to make the corrections.
^This. I also trust VGC to make downward adjustments to Xbox when it is needed. Additionally I'm not on another chart site, I'm on VG Chartz and will rely on the data they provide when making posts or threads.
...to avoid getting banned for inactivity, I may have to resort to comments that are of a lower overall quality and or beneath my moral standards.