I've typed this story so many times for these questions about crib climbers but here goes again....
Friend's child climbed out at 18 months. FIRST time she'd tried to get out. Fell and broke her arm.
Here's how I look at it: Put up the side of the crib. Look at the distance from the top of the raised rail to the floor. Now picture your child falling that distance. Pretty far for a small person.
Now picture him falling that distance onto his head. He could be injured -- at best. At worst? Can you even bear to think about it?
Keeping them in the crib once they can climb out is asking for injury. Parents want to keep them in the crib to keep them corraled. Crib tents are just a way for parents to try to get a few more months of avoiding the inevitable. Once kids can get out it's time to move them right away to a toddler bed or mattress on the floor or whatever. Their safety is more imporant than parents' temporary sanity and sleep.
You will have to work with him, possibly for months, as he learns to stay in his bed, not to roam, or at least not to come out and get you. Go ahead and switch him and be ready to walk him to his bed over and over. Do not talk to him or interact when you do; that makes it interesting for him. I know you had a bad experience with your daughter but this transition has to happen sometime. If he's climbing out, making the transition and dealing with walking him back to bed sure beats explaining to the emergency room doctor how he fell on his head while climbing out of his crib.