My opinion is that breed doesnt matter as lond as its doing what you want. If its a pup your after then get you friends to have a word with theres and see if they no anyone breeding worker to worker. I personally havnt worked a pure patterdae but have seen my mates worked, they all come with different temprements, some are too hard, some are mute and some are spot on. It all depends on what you want the dog to do.
I like a dog to push its quarry into a stop end and work it. Im not keen on terriers that steam in at full speed and just grab hold and take unnecessary punishment. That is just