If I had to guess, 12' x 12'. I listen at my desk, chair pushed back. I listen to mostly classical, especially baroque with lots of choral/vocal works included (cantatas, masses, oratorios, Bach's passions, etc.)
I love my current speakers, so I'm not itching to buy new ones. But interested in what 4w from the SEX can do... and concerned about the low sensitivity. These are year 2000-ish Paradigm Studio/20's v2 (with wood veneer, beautiful! matching Studio/80 fronts and a center; Her Ladyship did not approve of these being rears for a home theater setup, so I repurposed them for my office.) Best I can discern, from 19 year-old online reviews for the v3, is that these should be 90dB(room)/87dB(anechoic) sensitive.
Positioning is not ideal. A compromise, to be sure.