Working ability i can't comment on yet as i haven't seen one working yet! But hopefully there good as i have a pup bred that way.
Seen Wheaten/Greys work and have to say they give you everything a bull cross does but have a slightly better running style if that makes sense? All my Bull crosses where plodders, you would think it was a horse coming up field where as my wheaten pup seems to glide when running making hardly any noise.
The other most obvious thing they give you over a bull cross is the coat which is excellent. My Wheaten/Bull/Grey pup took to sleeping outside in snow over Xmas. T