Our plan (insert caution about the best laid plans ...) is to have the twins in our room/bed until they can sleep through the night -- which will hopefully be around the 5 month mark (No, we won't be doing CIO, but in my culture/family babies are generally able to sleep through the night at that age, so it's what we are aiming for). At that point it's on to their rooms and montessori floorbeds. One thing about floor beds is that you're not supposed to use them until the child can support their own head. As to the "being halfway across the room" issue -- that's part of the genius of it! If the entire room is childproof (or the entire area, baby gated, etc) then it's okay for the child to explore on their own. The entire safe space/room is just one big "crib" if you want to think of it that way.
There are some great blogs if you need resources, here are just two.