You must be a responsible owner though and make sure they can't get out or hurt anyone. My son wants boas. I told him I respect his right to do so but don't invite me for THanksgiving unless we are eating snake:')
Boas are nice snakes. I almost considered getting them when I started in the hobby. The one warning that I'd pass along is that any one of the red-tail boas may have the chance of reaching 12 feet in length. There's no way of knowing ahead of time whether that cute, little hatchling is going to reach that size someday. Many will stop around 8 or 9 feet, but some keep growing. If your son is serious, he needs to plan for the fact that his snake could be that big within ten years. If he's not certain that he can provide comfortable housing to his animal when it reaches that size, he needs to look for another species. If he's looking at rainbow boas or one of the other small species, that particular issue shouldn't be a problem. I love snakes, but I urge anyone considering them to do a huge amount of research. They are a perfect pet for me, but some people aren't in a good situation to be keeping them. I hate to see the heartache for the owners and the suffering of the animal when things aren't right.
Sorry for the sermon.
Bill