hi mark , in reply to the question you've posted , my dogs are predominatly greyhound , being 7/8th grey x 1/8 collie , and i , recognise them as lurchers , in that , yes they race at summer shows , to a fair degree, they are also very good working dogs aswell , as for that amount of pure bred blood not having any stamina , ( and im not having a go , just my opinion ) could your dog trot for around 5>6 mls 3 times a week @ 15mls / hr , id have my doubts , yes your dogs ( which nobody disagrees with are very good working dogs ) but would they have the same amount of stamina as , my , near