Any one by any chance have had experience with A7r mk1 or mk2 with the ZM 15mm F2.8? I can find some samples here and there on the internet, but none of them are full size nor have any caption/remarks with regards to the corner and edge performance. and lastly, any idea how the ZM 15mm comparees to the VC 15mm mk 3 on A7r mk1/mk2? i know theres probably only handful of people who tried these combinations in the world...but if i dont ask, i will never know, lol. thanks.