A high number of megapixels can also pose problems, as in the case of the first A7r and its shutter shock issue. Although it is one of those topics that can easily be blown out of proportion, it was definitely something to be aware of with critical shutter speeds between 1/100 and 1/200. The A7r mark II has fixed this problem with a newly designed mechanical shutter that is more discreet and has a longer lifespan (500,000 cycles on paper). With the addition of an electronic first curtain and a full electronic shutter option, I can safely say that it is very unlikely to have serious issues with shutter shock on the A7r II.
To be honest, I only struggled on one occasion while taking some shots of an artisan at work. I got better results once I set the first electronic curtain.