Need advice about my boys sharing a room

Ok so we have a 3 bedroom, I was thinking at first the baby would share with us, but now I'm thinking about giving out two boys 6 and 11, our master bedroom, so they can have a big space but share a room, and use the smaller room for the baby and me and hubby in the other room which is now my 11 year olds room. My hubby doesn't think,it's necessary. But eventually I'm going to,have to switch anyways when he or she turns 1 especially if its a girl she'll need her own room. And what if we can't afford a 4 bedroom at that time?! I don't think,it's that big of a deal,for two brothers to share a master bedroom with,their own bathroom!! I know this is America but seriously while famiies share a hut,in other countries!!! And this way instead of waiting till my baby is 1, I will have a nursery that I can have a recliner in to,make midnight feeding much easier on me!! What do you think