I can only go on the ones I've worked, I found collie lurcher I had with a tad of beardie in it had a much greater desire to want to hunt for a scent when there wasn't much about, he would work at a greater distance from me rather than checking on me every 2 seconds. He had more determination to get hold of what ever he was chasing. Maybe I just got lucky, but my god he could hunt,,,,nose down eyes up......I thought all lurchers were like this.....until I got another.