SP, I have been shooting my Contax G glass (usually only the 45 and 90 as the others have had issues in the corners) since the original NEX5. Then the NEX7 and started using it on this a7rII. IMO with my copy the 45mm lost something on the a7rII in the area of contrast and color compared to the NEX bodies and their 14mp and 24mp sensors. I was less than thrilled with the results on my a7rII. I could PP them to look as they did initially in the other bodies but I was really surprised I wasn't impressed with the initial results in LR6, C1, and even Aperture3. The FE55mm (at least my copy) once again gave me the CG45 color and contrast initial in both C1 and even more in Aperture. I retired my 45mm back into the ContaxG2 kit and most likely if my next purchase is the 90mm macro(still debating for the a7rII if my next lens will be the 90mm mac or the 70-200f4 even though I am almost totally convinced my long glass usage will stay with either my a99 or a77II and 100mm and under the a7rII so the 70-200mm f4 is getting less and less likely) the 90mmCG will also return to the ContaxG2 kit. I am thinking I will be pretty much set with the 16-35f4, the 55mm f1.8, and the 90mm mac for a hike in a7rII kit for scenics.
The techart adapter price and the issues trying to manual focus with a smaller wheel pretty much loses it's appeal compared to using the newer OEM FE glass and the results I am seeing with my own results so far.