Thats A sweeping statement to make fence_hopper, as with all mongrel "lurcher" breeding you cant say how a dog will throw, i myself have a Bull/grey X Wheaton/grey, from your statement above people would assume that this would be a beast of a dog,
Well he`s 24" to the shoulder and is quite often mistaken for a saluki X , and he can fair shift a bit too...
I`de say it would be a good idea to use a wheaton/grey across the bitch to add a bit of substance, maybe a rough coat, and perhaps a good dash of prey drive, but i repeat when breeding mongrels it`s in the lap of the gods as to what you`