sean

I returned mine. Too many flaws for reliable professional use. Of course this is just my opinion and some folks will go out to do wonderful things with this camera. 
I've come to believe that Canon is being a lot more serious about their hardware. They don't care about hype, they care about producing professional tools, while
Sony seems to have in interest in dominating the consumer market with "rushed-to-market" bombs that blow away the competition on paper only.
 
I'm waiting for the 5d IV or a used 1Dc for 3500 Euros 

quick update before the full test:
Overheating seems to be less in FF mode. I've reached the 30 minute mark without a heat warning in FF mode, whereas in S35 mode heat warning was reached at about 15 minutes and the camera shut down at 20 minutes. IBIS was on for FF test, but camera was resting on the table.

picked up my a7r II today and the very first thing I did was see how it handles long takes. 
20 minutes of record time in 4k 100 Mbit before the camera overheats and shuts off. 
You get a warning message something along these lines before it goes blank though: 
"Camera too hot. Let it cool down." How coy Sony. 
 
 
 
This has to be addressed or I will have to return the camera. The s35 Jello is disappointing, but something I can deal with by sticking to FF mode for most of my shots. The camera overheating makes it a very bad choice for any kind of documentary or live recording. Its one of those things you can't explain your client. Imagine missing the moment because the camera overheated in room-temp.
 
I am sure it can handle longer takes in 1080p, but lets not try to find reasons to make something broken acceptable. I hope there is a way Sony can correct this, but it seems like more of a heat sink issue rather than something that can be fixed with a firmware update.

quick update before the full test:
Overheating seems to be less in FF mode. I've reached the 30 minute mark without a heat warning in FF mode, whereas in S35 mode heat warning was reached at about 15 minutes and the camera shut down at 20 minutes. IBIS was on for FF test, but camera was resting on the table.

quick update before the full test:
Overheating seems to be less in FF mode. I've reached the 30 minute mark without a heat warning in FF mode, whereas in S35 mode heat warning was reached at about 15 minutes and the camera shut down at 20 minutes. IBIS was on for FF test, but camera was resting on the table.