New to Harry Winston watches, and this question bothers me a lot. The Ocean Diver looks quite similar as Z2, with only (what I can see) differences in color and metal. A director at HW Boutique told me that the project Z is limited edition only, and they are barred by Swiss law/rules to make more. So that means if HW want, they can make Z1-Z4 under their regular line, and all they have to do is alter the color/metal? Thanks!