I'd go for the Ace. It's a current model, lighter and easier to swing, less settings to mess with, and cheaper batteries. The down side.... I can't stand yellow. Some people have difficulty pinpointing with it, but I don't think that would be a problem with practice. The Ace has a quicker response time, so in a field of trash, that can be a blessing. I think the Ace also has better ergonomics and it breaks down into a smaller package than the BH. The BH is a discontinued model, is somewhat heavy by current standards, and the 9V batteries tend to be pricey. The accessories are cheaper, however. I'll catch flak for this, but I feel the BH will go a little deeper when properly set up and used. Whatever your buddy picks, he needs to make sure it's right for him, i.e. he is comfortable with it and its operation. Just my thoughts....