Will be nearly 24 hours soon at 6 hpm. Not got anything yet .... but happy to keep going for now. Have another 20hpm to switch on to this tomorrow 
could you give us your spec of cpu ?? to have a high hasrate like this
Currently running:
i7 2600k at 4ghz - approx 3hpm
i7 3720QM - approx 2.6hpm (i know, i know, but it's work's laptop
)i3 3217U - 0.39hpm (Intel NUC)
I have a small set of 20 machines running Haswell i7s to switch on to this tomorrow for a little while. Only dual core so I'm assuming about 1hpm per machine.