Results: The hub works great. It powers a Raspberry Pi with no backfeed issues. I only have 4 sticks, but I have no doubt the hub would run 7 of them, as I opened it up and found 2x 5V/3A regulators.

I plugged it into my Kill A Watt before work this morning. It was reading about 22 watts even. That's a 12V/12A PSU, USB hub, Raspberry Pi, and 4 USB ASICminers.

The 12V PSU is certainly not running very efficiently at such a low load. I should be able to save a few more watts by using a smaller power supply. I'll find a suitable wall-wart and update. I'll take some measurements on the DC side as well, which might be more useful for those who intend to go solar.