is there a particular reason you ditched the terramaster?
I ask because I've been considering buying one... I currently have a 2-bay synology and wanted to move to something with more drives for better resiliency & cheaper upgrades - 4-bay 1u seems to be the target for my use case. synology has been making decisions I don't agree with for supported hardware, and if I want to get a rackmount option there aren't a lot of choices: roll my own with a questionable chassis off amazon, break the bank on a 45drives setup, or go for something like a terramaster or qnap.