I had HIGH hopes for these cameras. They really represented everything I wanted in a camera on paper. But after playing with them for 30 mins at PhotoPlus, I'm no longer convinced.
Not going to dwell into the well known specs. Here are the factors that DIDN"T work for me:
1- Cheap and light build. Defintely cheaper than the RX1. Not in the same league as Leica Ms. A7R is slightly better with metal dials, but both felt hollow
2- Annoying UI, same Sony UI here. If it works for you then great, it doesn't work for me
3-Lenses felt HUGE. the zoom was so large that it may well belong to a DSLR. the 55mm 1.8 Zeiss was smaller, but still bigger than the RX1 lens. Feels more bulky than the Pentax K5
4- Phase detect AF on the A7 doesnt' work well. I tried to track people walking toward me and it hunts back and forth every time I try. This is very bright indoor lighting
5- The sony guys admitted that they didn't release a 35mm F2 because no one whould buy the RX1s.. While I appreciated their honesty, it sucks! The lack of lenses (and expense) will be the archilies heel for the Alphas. Sony won't have a decent line up for another 2 years and by then the cameras will be obsolete. This is the single reason that I decided to keep my M4/3s
Now I was impressed by the manual focus assist on the A7s. It tracks subjects in real time and puts the focus pane in RED. This is how Leica M240s are supposed to work. But I tried a M240 right after I tried the Sony and the Leica felt sluggish and unuseable. It took me less than a second to manual focus spot on with the A7. I was promised that this feature would work on leica legacy glasses so focusing shouldn't be an issue.
The EVF was good and fluid, but nothing to be crazy about.
The conclusion for ME is to wait. I'll wait until at least two fast primes come out for the A7 before I take the plunge. By then the camera should have depreciated quite a bit. In the mean time perhaps snap up a Rx1 as they become cheaper?
Buying it to use with my Leica M glasses doesn't make sense. It will take longer to focus despite the focus assist feature, and many leica lenses are reported not to be working well with A7 sensors. Stick with your M9s if you want to use Leica lens. I suspect the A7r will outresolve older M lenses as well