Hello Archie. Yes I do indeed use a Melco N1ZH/2. The new one is actually the NIZ EX. However the EX suffix mainly ( wholly) refers to the incorporation of the SongKong music library metadata administration system. That would seem to mainly affect the N17 when used as a USB streamer ( using the Melco controller rather than Mosaic) so that probably moves far enough away from IMO the best way to use it in a dCS context, using ethernet connection to the dCS streamer ( or network player if you prefer), for me to make a comment. I am confident enough about my metadata ( after huge amounts of work given my library is mainly classical music) to think SongKong has less relevance for me.
I have been running the N17 as a NAS for around 18 months and have found it totally reliable and simple to use. A main advantage is that to connect the Melco to the dCS network player ( in my case Vivaldi upsampler) you do not use the router. It is a direct connection. This has SQ advantages in practice even if it is not that easy to deduce why from a theoretical standpoint. However the internet connection is, of course, via the router or (preferably IMO) using the Melco S100 switch but that is an additional expense and controversial ( though the controversy seems to disappear on the part of those who have actually tried it).
Additional advantages are that it is styled as an audio system component rather than a stray piece of IT equipment and is silent. No sound at all of discs spinning unless to put your ear to the case when you can hear a very faint swishing. So you can place this NAS alongside the rest of your audio components.
I am very happy and if I needed to I would buy one again.
Ripping will be a similar procedure to the one that you currently use although I use dbpower amp with Perfect Tunes meaning that much of the metadata and almost all of the artwork is automatically entered. I do need to edit here and there but the overall work is reduced. There may be case for the SongKong application in this respect but as I do not have an EX version of the N1 I again have no comment.
You will need a subscription to MinimServer 2 and download MinimWatch to your PC. There is a dedicated Melco version of MimimServer which Melco will have pre-installed on a new piece as it is now their default UPnP server software . However I suspect that running the basic version without a subscription may prove of short term interest only as you will probably prefer to have some of the extras available.
One tip which I have read both in reviews and have heard from a Melco engineer and can verify , is to use the option of RAID 0 for best sound quality. That also allows use of the full storage capacity of 6TB ( N17), way in excess of my ( or presumably your) current needs.