I got the chance to spend time with the Sony a7 III in Las Vegas and then again here in NYC; and after all the time that I spent with the camera I am not totally sure who the customer is that may purchase it.
There are three mindsets here: those who need really fantastic high ISO output, those who need high resolution, and those who need a combination of both for work reasons. All of these are fulfilled by the Sony a7s, Sony a7r and the a9 respectively. But with the Sony a7 III, you've got a camera that is more or less a very stipped down a9. Sony targets this camera to enthusiasts though it's more than good enough for professional uses providing you're not taking it into a lot of dust or rain. To get the most from it, you'll need to pair it with some top notch glass. It can make for a solid second body and can surely fulfill all the needs of most photographers. But as I found while being a Sony a7 owner and upgrading to the Sony a7r III, there is a chance that its light isn't going to shine as bright as the other options in the line up. . thephoblographer.com