384Mhash for ~$2100.
10 months to break even at 6000 difficulty $.10 power
25+ to break even at 12k diff and $.10 power.
(according to Coin Warz calculator)

I'm sure your numbers are right. But I think you are assuming there will be no virtuous cycle provided by a more secure blockchain. A Chinese company committed time and people and money to design, tapeout, manufacture, characterize, and bring into production an IC that is dedicated to mining X11 secured blockchains. This is capital intensive work. This is not rolleyes. This is a vote of confidence in the future of DASH.
my eyeroll was really more for the fact that X11 is supposed to be ASIC resistant. If the algo is changed to defeat the ASICS then the above hardware is a waste of money for X11 miners and nothing more than yet another attempted cash grab by some Chinese company trying to take advantage of a situation.