A 0.5% bulk discount on over 100 units. 
I've been lurking for a while and this urges me to add my voice here
Avalon6 and BitMain's S7 are overpriced, too much, they're actually priced for 2-3c/kWh electricity.
I mean, BitMain in China does not have access to such cheap electricity (I don't have any proof, just long reads here about cheapest electricity in China) so they have to be sure that nobody can earn more than themselves when selling an S7.
BTW, they sell it on Hashnest as well, so Hashnest's price is a little lower since you're paying .10c/kWh there.
What we should find, IMHO, is cheap electricity, like .05c or .04c and a bunch of second hand S5s or SP20s, which are overpriced as well (from the WTS offers I see here on bitcointalk), but not as much as a new S7 and should possibly ROI no further than April next year and be able to be marginally profitable (thanks to cheap electricity) beyond next halving.
Spending 1600 USD/unit now to earn 98 USD 400 or more days from now... well, is not that thrilling as a proposition, not to mention that a single failing unit wipes out the earnings of 16 more units.
spiccioli
all profitability numbers are bogus anyway with btc being $380 one day and $295 the next.
the only play here is for halving-associated btc expected jump.
So, you accumulate coins like there is no tomorrow, then sell some.
If no jump, then profits would be marginal, if any.