I have 1.5 Antminers.
One that always performced fine, and one that always performed badly, with the 2nd board shipped back after dying, and now supposedly lost in mail. The bad performing board is april 2014 issue.

Got all 3 board modded to < 3kOhm, and Now I am running around 248 Watts for 210 GH/s (GHash.io average, 1 day). The single board is doing 65 GH/s, the fullminer is doing 145 GH/s. Both do have some HW errors, < 1%.

So I am at < 1.2W/GHS. So even the relatively high power costs here allows me to make a profit for a few more weeks/months.