A separate backup NAS would better than nothing. If losing your data would be a disaster, then don’t overlook backing up your data in a separate location (either at someone elses house or use a cloud backup provider like Backblaze) incase of a fire, etc.





If it works for you, there’s no reason not to keep using it.
If it looks like an upgrade in performance and simplicity and you think it’s worth swapping, then you could consider it, though personally I’d wait until it’s a bit more mature/proven (maybe it is already idk).