We did Disney on a budget several years ago when my kids were 4-10 years old and stayed at the CBR.
We actually squeezed a couple extra kids more that we were supposed to in that year, and no one questioned us, however I did feel a bit conspicuous. Not sure how common it is.
The rooms were pretty small and we felt pretty cramped. However we were hardly in the room. Since that vacation we have always gone with two rooms anywhere we go, or a two or 3 bedroom condo.
Have fun and do what you think is best for your family!