My daughter is 7, my son is 5 and they share the sofa. We have never gotten a studio, always the 1-bedroom (can't do without the washer/dryer), and soon we'll be moving up to 2-bedrooms. Of course, we also recently bought more points....
I want my kids to be comfortable even on vacation. My son is a total bed hog, and they really don't sleep comfortably together.