@ Skycat.
I'd always go for lurcher to lurcher,that would be MY preference. Provided you know the linage of the dogs, no matter what is in the crosses your using, like the ones mentioned above, with a fair percentage of sight hound, your chances of producing a 'runner' AND a worker will be high. Looking for the best attributes of the other dogs in the mix can/would be difficult BUT what you should be looking for is 'working ability'.
Though, if you do have a good enough dog to breed from but you are unsure of its background or if maybe its a more speedy dog your after, then using a greyho