Thanks to everyone for your comments, and particularly Russ. A great forum with helpful people!

Russ, I've asked a couple of questions below and will much appreciate further comment. Thank you. Jeremy
Originally Posted by Ratbert
Another possibility is to clone the disks in your MD600 using an Icybox, this would give you an exact copy of the disk in the event of failure, this is permissible as there is no Meridian IP stored on the disks.
Never having heard of an Icybox I have googled it and note that it seems to be essentially an external hard drive with two or more interchangeable drive units. Is there any particular reason to use something like this rather than a standard external hard drive?
You talk about "cloning the discs in my MD600" but I'm not sure about the use of the word 'cloning' in this context. Does it mean that I would remove a HD from my MD600 and put it in a Icybox to copy to another drive, or does it mean using the export facility rather than the backup facility to copy FLAC files to an Icybox/external hard drive, thus avoiding the Meridian IP? I suspect I'm a bit confused here!

Originally Posted by Ratbert
As far as Roon and storing files in separate folders you can achieve much the same in Sooloos by using tags, if you tag all your classical files with 'classsic' blues with 'blues' and so on then you can use focus to look at just one tag or any combination of tags.
Sooloos tags and focus are useful, but ideally I would prefer to be able to locate albums of different genres within discrete folders in the main menu rather than searching for them subsequently. I guess I'm being a bit pedantic!

Originally Posted by Ratbert
Reasons you may want to consider Roon are ongoing development and choice but if you are happy with Sooloos then why change, try a Roon trial and see what you think, plan it for example Server, music, storage before you start the trial.
I assume from your comment that Meridian are not likely to be spending much time on ongoing development?

Control:PC, MS600 & MD600, Audio Note M5 pre-amp, Conquest power amps, Magnum Dynalab MD108 tuner, Duevel Bella Luna speakers. Approx 2000 albums on Sooloos - wide range of genres.