I am not arguing with you but, @ 500GHs these units will net you $18/day and assuming another 25% diff increase $14/day. After that, assuming continued 25% diff increases (which I do not expect) it would get very ugly.
No they wont, at current 504GH/s will only gross $11.01/day that's assuming zero power cost and zero pool fees! Net of course is substantially less than that.