Well I say go for it. I was a bit like you after 3 and then we decided not to have 4 and my Dh had the snip! Big mistake!!!! He had to go back...get unsnipped so we could go for that much cherished 4! 4 works for us...even with the big gap...and we already had the bigger car and while our middle two daughters do share a room..its not a problem at all..they actually wanted to anyway.

Jo