what do people mean when they say a dog picks its runs? if you mean a dog will sometimes chase and other times not, or a dog will run well early on but fade later in the night, or a dog that is unreliable or something along those lines, then this could be any dog not just a collie cross
but if you mean a dog which will run hard at rabbits in the open but just watch those which are siting in the burrow mouth, or a dog which will simply calmly stalk a rabbit 5 feet out from the hedge instead of plunging into the cover 10 seconds after the rabbit has gone, then i dont have to much problem wit