Personally I feel an underground fence is a waste of money. They will work in some dogs (especially if you start the training at a young age), but in a lot of cases, your dogs learns too get by it very quickly.

If you want your dog to run loose AND want him to stay in the yard, better look into building a fence. Like others on here, there is nothing wrong with kenneling your dog as long as they get their share of "active" time.