Took some time the other day to fire up RS units and see if the drives are fine as well as to try and use Hynix ECC RAM that I got.
Well, the good news is that RS units are working just fine. 4Gbit LAG also detected and working as intended. The bad news is that Hynix ram that I have is not compatible. Voltage and latency are fine but the ram is dual rank so not working at all. NAS won't boot.
No matter I will get some more compatible ram in the future when time comes, at the moment 4GB will be enough to host the content that it needs. When Docker farm will be moved from 918 then I will get some sticks in there.