In determining the room size for selecting a system, should adjacent rooms with cased openings be considered. For example, my great room (where the system will go) is about 20*18 with 9' ceilings. It has a fairly sizable cased opening to the dining room (14*12) and smaller cased openings to the foyer (8*10) and kitchen (14*25). Since sound will leak into these adjacent rooms, should I consider their square footage in determining the right system?

I just ran the system configurator and, based on a 250-500 sq ft area, it recommended the Epic 60. I am wondering if I should have used a larger square footage.