I just wanted to let you folks know that you can expect more QC problems with Sony Zeiss ZA lenses than you may be accustomed to.
I have been using the Sony A900 since 2009 and I had a serious problem with my Zeiss 24-70 f2.8 ZA.
I know one should not expect this issue with a $2000 lens, except my lens had a serious wobble in the lens zoom barrel, even at the closed position.
While Zeiss can design superb lenses, it seems the Sony QC is not up to the mark!
I have also spoken to other owners of the lens that had the same issues.
I love Zeiss optics. I just wish Sony would have the same excellent quality control on these lenses that Zeiss has on the manual focus lenses for Canon and Nikon.
I will keep my fingers crossed with the 55mm f1.8.
Wishing you all good luck,