Well as I understand it the 218 is not equipped with RAAT. So that also puts me off a bit. And I have been told, and read threads here saying the same thing, that if Sonos and a 218 are both served by Roon on the same system that the 218 is inclined to drop. Which would be extremely annoying

ROON Rock on an NUC across the systems
Sitting room: 218, DSP7200SE
Study: 218, Quad 303, Spendor BC1
Bedroom: Musical Fidelity A3CR, Chartwell LS3/5a
Various Sonos boxes in bathroom and spare rooms