Thank you all for the responses.

As it happens, I have my Roon core on an 8th gen NUC with i7 processor, 16GB of RAM and 256GB SSD.

Unlike so much of Roon (that is a purely personal observation) I found putting Roon's OS on it to make a ROCK was extremely straightforward by just following the very clear online Roon instructions.

My point about Roon on a QNAP is that while it might be a bit slow if you have the sort of enormous collections that some people evidently do have, you do have a choice if Sooloos is extinguished.

Cinema/Music: Trinnov Altitude32 8-16,218,Cloud 4 channel, Marantz UD5007,DSP5200SE(2+C),DSP3300(4),DSW(2),271,MShort Ceilings,AppleTV 4K
TV: Marantz SR7013 Wharfedale Diamond 9x4+Celestion(C)
Music: Roon,i7NUC8gen,QNAP TS253A, Sony Scala, MS200, Garrard DDQ650,Wharfedale Diamond 12.3
Kitchen: AD88 (bluetooth via i80).