Well, not sure I am moving yet. I will try some comparison shots tonight, I hope.
There is nothing wrong with the A7S, per se. It is my particular circumstances. I specialize in a certain kind of night photography where I MUST-MUST-MUST have built-in GPS, preferably with compass, and have that data punched into the image EXIF. Sony did not provide it, promised they would, have not so far, and may never do it. The market is too small for third-party providers. If you look at some of my recent stuff, you can tell that location is important:
Ritual Landscapes at Night - WesternRockArt
most of which were taken with the A7S and various manual lenses.
Also, I tell you, the ergonomics are not that good. The buttons and controls are poorly placed, and impossible to find in the dark, yada yada yada
The K-1 solves a lot of these problems for me, hopefully the image quality is there. I need really low noise, and, with the A7S I can shoot anywhere from 2000 to 51,000 ISO and the noise levels are about the same.
But, the damn thing is so small, it can be hard to handle, particularly because the FF lenses are about the same size anywhere. On the otherhand, when I pick up the K-1 it seems to weigh about 100 lbs.
We will see.