A good digging dog is something that can be used regularly, you need a steady type that knows how much pressure to put on, why keep something that gets used once and is out of it for a month. When your out 3 times a week through the season you have to keep steady types or you end up having to kennel 20 plus dogs! Other main attributes are good nose, to stay all day if they have to, manners - quiet on the hole when not used/ no fighting with others. And not over searching - fair enough have a look round but when they keep going round wanting something to be there for hours on end is a real faul