Sorry for intruding in Your thread, but as I see that here are some people that knows this stuff, I wanted to ask:
What is currently most efficient ASIC chip for BTC mining? Or, who makes the most efficient mining hardware at the moment?
Most current in production you can get on BTC is S7's and Avalon 6's. There are some like bitfury that have shown proof of concept.... if they are on shelves in a data center no one really knows.
But those 2 are the best you can get currently that are sold to home/hobby we know that much.