on ptr, i tested whether a a dual wielder or 2hander will be the faster pvm'er in mp5~7 and here is what i found.
below is the skill setup i use which incorporates speed when farming.
http://us.battle.net/d3/en/calculator/monk#aWgSck!Zbg!abYcZa - dual wielder Ef + WKL
http://us.battle.net/d3/en/calculator/monk#WejSck!cbd!bbbYZa - 2hander lifesteal Skorn
items on both setup are all the same. the only difference is the weapons.
mp5dual wielder and 2handers are very close in terms of kill speed and movement.
killing normal white mobs takes about 2~3s for a dual wielder while it takes about 1 sec for a 2hander to kill by dropping a bell.
for elites it takes about 5s to kill when dual wielding while it takes 2bells(about 2sec) to kill with 2hander.
overall, both setup feels fast.
mp7at this mp level, i felt something different between the two
killing normal white mobs takes 4~6s to kill with a dualwielder but it still takes 1bell to kill with 2handers.
for elites, dual wielder takes about 15 sec to kill while it takes 3~6 bells(which takes about 3~7s ) to kill with 2handers.
overall, it feels kinda slow with dual wield while mp5/7 feels almost the same with 2handers.
Ghost, have you tried a normal dual wield build with like bells instead of blind or BOH?
and maybe submission over overawe so you get slightly more dmg with out constantly spamming it.