Big boy bed -- size? with crib?

[hillview]

As I mentioned in PP we are moving and DS is getting a big new room. Was thinking of getting a big boy bed for the room but keeping him in his crib. Is that a good idea? Thought it would be good to get used to before moving him into it and nice to fill up the room.

Also the room is large enough and there is a bed nook that holds a queen size bed -- is that a bad idea for any reason?

TIA!
/hillary