I am still not convinced about ROON. Volumio has pros and cons. Roon has his cons. I miss music services integration in Roon (only Tidal/Qobuz). That is a pro for Volumio.
Roon has more available apps (appletv etc) that is a pro for Roon.
Volumio has airplay. Roon does not.
I still can not decide which music software to use. Volumio is much cheeper.
It was an easy decision for me over two years ago.
To clarify, I need to run convolution with my DIY full-range-line-source speakers.
Volumio would allow for only one filter sample rate and additionally the DRC plugin ran very glitchy - constant fiddling guaranteed.
Roon just works.
I’m not sure if it’s the best forum to ask about it 
For me it’s rather LMS vs Roon.
I’ve tried Volumio but first I wasn’t able to install Spotify then to switch from terminal to GUI and finally while login to Tidal i got an error that account is blocked. Too many errors for me.
LMS started working instantly
I moved from Volumio to Roon several years ago. Main reasons:
Both Roon and Volumio have changed a lot since, so the tradeoffs might be different now.
The one that suits your needs the best. For me its Roons first class multiroom and device support as it allows me to play to my Naim Uniti Atom, Squeezebox Touch, Chromecasts, pi’s, phone, DAP from one app and not use DNLA/UPnP and it’s not limited to 6 devices. It’s also capable of running on more platforms and performance wise is leagues ahead at dealing with a large library… It also allows me to have one music library that encompasses streaming and my own files seamlessly I can’ edit and curate this library with much more control than Volumio can ever provide.
I see this all the time and I can only assume its confusion on how Roon works. Roon does not need to support Airplay beyond its current ability to stream towards an Airplay device (which it already does, maybe Airplay 2 would be nice but different topic).
What you want are endpoints that support both RAAT (Roon native streaming) and Airplay. Pick your endpoints carefully and you’ll be fine. Roon doesn’t need to be, nor should it ever be, an Airplay target.
Was just going to add, you can run both concurrently. I run Roon on my NAS and have volumio running on my endpoint raspberry pi hooked up to my amp, with the roon bridge extension. I’m able to use roon for my library listening and can still use volumio for Spotify connect and anything else
You use two abo’s? Volumio and Roon?
I have to choose because I running Roon or Volumio on Nuc10i3. Dac is connected to Nuc. My library is in a secundaire internal hard disk.
Volumio 3 is better than before but far from perfect. Roon comes close.
I’m not able to obtain the same details and sound stage with Volumio. My conf: RME ADI2 + Audiolab 8300 + Wharfedale Linton. I’ve decided to return back to Roon. In my office Volumio is ok… but just in my office.