According to some people that have Angband (aka little French kid with a big mouth) as friend on battle.net, he only does Malthael when he post paragon level pictures for some reason. Maybe to fool the world because there is a little circle of hardcore D3 players that knows of an huge EXP exploit that they dont want Blizzard to fix... They must be far over 10billion@hour with the paragon level rate they are at.
But, you can look at Gabynator, he does paragon levels faster than Angband and he even streams his sessions (when he plays manually)