The Antminer R4 joins me on my Bitcoin mining journey and it is still too early in my experience with this miner to tell anything but a short story about it. But I can say these things right now: It is significantly quieter than any other powerful ASIC miner and it is more electricity efficient than any other miner.
When the R4 is running at 8.7 terahash (TH/s) it still puts out quite a bit of heat using about 950 watts compared to something like 1300 watts for the Antminer S9 (13 TH/s) and the previous model Antminer S7 (4.7 TH/s).
At the moment it is creating the equivalent of about 0.15 Bitcoin per month (in a mining pool) but this will go down at the next difficulty increase.
I really like this machine and though it is not as quiet as the Black Arrow Prospero it is much more powerful, productive, and expensive (unfortunately). Also unfortunately, I see on Bitmain’s website that they have been out of stock for a while and I am wondering if this means they will not produce them anymore. If not, then miners who want a powerful Bitcoin miner that is relatively quiet will have to buy whatever is available on eBay, which is mostly used stock. If you want a powerful miner and don’t care about the noise then get the Antminer S9 which you can get new from Bitmain, on eBay, and on Amazon.