Funny you should say that, because my findings show that~

They are almost the same size. The non racial butt, using the moonfire tanga, is rounder and slightly larger, the other butt is slightly shorter, and smaller, and seems to have less polygons/curves, lol.
I proved myself wrong, the racial gear isn't any bigger (if anything, it's a little smaller), but it does have a different shape. Science!
Also, I don't know why I spent so much time doing this, as I don't even like looking at women's butts.