Disclaimer: During the PSU supply crunch, I got a few "Ethereum PSU" from China.... until I get the EVGA-G3's and server PSUs.
So far so good but I am not very comfortable with the "poor man's PSU" so I use them when only needed and did not beyond 50% of the alleged watts rating. It however got all the cables, connectors required up to 6 x GPUs (6/8pins) or 3 x GPU (2x8pins) -- its the real deal.... but I don't recommend it unless you don't have any other choice.
Form factor on those "1800 watt" PS is WAY too small to be a legit 1800 watt - and I also find the "90 Plus" certification an issue, as there is no such certification.
They look suspiciously like the 1100 watt PS I have in some of my Innosilicon A2 units.
I'm not sure I'd trust them for *1* kilowatt 24/7.
The "1600 watt" PS are big enough they MIGHT be legit.
I have 4 of this Ethreum PSU running 24x7 for 2 weeks now, isolated in a different rack with its own 20amp circuits... running 500w to 700w at max and never beyond that. Fingers crossed -- all is well. They will be soon replaced by 94% Platinum server PSUs with pico, bb kit.
Compared to the EVGA-G2-1600w, its almost similar in size... but top rated PSUs like EVGAs have very high quality parts, sturdy build, 10-Year-Warranty, etc..... I have 12 of them in my farm 24x7 since Jan 2016 and all are still alive even today. The fat C19 power cord itself is an amazing piece of piece of engineering.