Everybody til there own brother worked a coursing greyhound bitch for a right few seasons day and night with no problems with joints feet etc are stamina an could turn aswel as alot of lurchers.. And took any game that was asked of her.. She was lined with a half x bull grey to half x bull grey dog 27ins to the shoulder.. Way I see it to dogs proved there self out in the field with no doubts not to breed them cant see why there is an issue with the pure grey when you have a good one its a good one..!!