Hey J.!
Although we did not care for the toddler bed, when my twins did sleep in them the transition went well. I would do the following:
1) Let him choose his sheets and a special favorite pillow case. This is a big boy bed! Make it special.
2) Next, don't get rid of the crib right away...make the transition smooth. I would start out sleeping there at night and then gradually put him there for naps as well. (Or toddler bed during the day, crib during the night.)
3) When you put him in it, stay for a few minutes. Make sure he is tired and has everything he needs. (Stuffed animals, a sippy cup of water on the night stand, favorite blanket, etc. Gradually go to the door. Wait a couple minutes. Then ease your way out the door as he is drifting to sleep.
4) I would also put up a baby gate in the doorway of his room. This will help you keep him contained, or at least hear him if he tries to get out! I always said, child proofing never worked on my kids, it just delayed them long enough for me to get to them before they got into anything! LOL
Lastly, I wish you luck. It is never easy making these "big boy" steps! E-mail me with any questions! I'm happy to help!
~Lee