I once heard a saying, 'when in doubt, go back to the greyhound' I was never in doubt with my lurchers, and I went 7 generations before I put a greyhound back in, and pups in the 6th generation were some of the best all rounders Ive seen on. Yes you always have to go back to 'root' stock at some time, but sometimes in lurchers a good first cross can be a most useful animal to go back to as well, just a thought..