Hi Mathew,
For me, I wanted my LCR to be 100% identical, even down to having all three vertical. As I didn’t have room for 3x towers, and didn’t actually feel the need for towers as I’m running subs with home cinema and stereo content, I went for 3x 1723 Monitor S. I would have gone for the 8” 1723 Monitors if I had more room to play with, however, as per the below video I don’t have much space. ;-)
In an ideal world, I’d love to have Monitors for all of my bed layer speakers to get a seamless experience.