This lens was quite a surprise when it arrived at my doorstep. Very small and light and fits well on the Alpha cameras. It performs quite well on the A7 but I've still to test it on the A7R. To be honest I've been using the A7 more than the A7R because I think I'm getting better results with it. I.e. Better percentage of keepers. I think there's something in the shutter shock theory now coursing the Internet. I'll have to do some more testing on this though when I have the time.
What I'm planning at present is test all my favourite lenses I've using on my Nex-7 on the A7R but I can tell you now, those lenses will not perform as well on the A7R. I've noticed this with the A7 and it really stands to reason, The Alphas are full frame where the Nex is only APS-C. Lenses have to be very good to perform well on the A7R and it may be that I only have a couple of lenses that will pass the test. I'm not going to sell my Nex cameras as I have a few lenses that I just love using on them, especially on the Nex-5N. This camera produces very good image quality, even though many will call it an OLD camera nowadays. It's small and my Voigtländer Skopar lenses fit nicely on it because the lenses are very small indeed.
The reson for posting the above image taken with the Voigtländer Skopar 20 f3.5 SL is to show the quality of the converted image to B&W. I seem to be getting better conversion results using a gradient map with these files, rather than using the Nik SFXII plug-in. The image was taken on a very dark, windy and rainy day; just perfect for this type of image. Hope you like it as much as I do.