Labradoodle crate size

Question
We have a 45lb male labradoodle and we are trying out a bigger crate for him.  He could stand and turn around in the older one, but his head touched the ceiling when standing and could not completely stretch out on his side if lying down that way.  The new one is huge, his head does not touch, and he can lay however he wants.  My question lies in which one is better?  He seems to be messing up his blankets in the new one to get them to be "snugglier" like his old crate, and still often lies curled up even though he has tons of room.  Can we put him in the old one, and how long should we test out this new crate?

Thanks!

Answer
I start puppies in a 24'' crate and later move them up to a 36'' one.  They take awhile to adjust.  I remember Lucky crawling into the old crate for a nap after he was so big, his head stuck out.  

If you ever think there is a chance you will fly him somewhere, get him used to the one his head doesn't touch now.  The airlines require the dog to be able to stand up in the crate.  That won't do any good if it isn't a plastic crate.

Otherwise, it looks like you could do either.