Worker to worker means feck all, apart from the fact that both parents were worked. It doesn't follow that all the pups will, or even be suitable for work. Plenty of working/coursing/racing champions etc in both dogs and horses, bred from parents which have never worked, coursed or raced prove it
If you just want a few rabbits and you just buy in all your dogs thats fine,but if you want the line to go on then you need to get the best rootstock from the beginning,not a quick fix from the lurcher supermarket (hancocks) Theres a dog on here owned by BIRD I think. Thats a proper collie/grey