My best ever catch dog was sired by hancock's Taffy. His dam was a very greyhoundy mongrel lurcher. Definitely the fastest lurcher off the mark, and up to about 200 yards, I've ever owned. I suppose not strictly a 3/4 bred, but you'd think his dam was a greyhound, so more or less a 3/4 bred.
I caught loads of hare and deer with him.
Seen quite a few 3/4 breds from hancocks. Can honestly say I'd be happy to own all of them. Very versatile, efficient working lurchers. All border collie bred.
Don't know what the situation is now with them though. Was it last year they stopped bree