Thanks everyone for your really lovely comments

I agree that Zak's colouring and markings are striking, and I often get asked about him (and it is usually his colouring that people comment on first).
I was recently told of another dark sable workline GSD looking for a new home who looks similar to Zak, and I was soooo tempted

but common-sense has prevailed and with three GSDs and one BC already, I really don't need another dog - however much I loved the look/sound of this lad.
As much as I adore my longcoats, I think it will be workline all the way for me from now on. Although I am "dogged up" well and truly for the forseeable future at least