The wfs ones are distinguishable from Caithness ones. The finishes are different, but I cannot for the life of me remember what the difference is.
Caithness have flat polished bases and polished rims. I can't lay my hands on one right now to check for bevelling on the rim,
but I think there is.
(I've just checked your pics)
I can't remember how the wfs ones are finished.
Colour is always a good clue - both Caithness and Wfs are quite specific about those.
I think the wfs ones might have bulgier bottoms although Caithness did a shorter, wider and bulgier version too, it was designed by Charles Orr and is no. 4033. (p 27 of Mark's book)
They are quite different to wfs.