I attended a 3rd birthday party for my nephew yesterday and decided to bring along the G7X to get some pics of the family (as opposed to my Olympus EM10).
Overall was very impressed with the responsiveness of the camera. Setup a Custom Mode that automatically set the camera to Av mode, Aperture of 4.0, Flash set to ON (when it is popped up) and Face AiAF (which is not my normal Small Center Spot Only but seems better when basically taking pictures of faces).
What surprised me is even with very good lighting in the room and using the flash, the camera was constantly choosing a much higher ISO - almost every flash shot was at 640 - than I would have expected. My EM10 and the Stylus 1 (that the G7X replaced) rarely selected an ISO higher than 200 when the flash was being used.
BTW - I have the AUTO ISO flash setting set to STANDARD rate of change - but not sure what effect that would have had.
Now I know that I could have used manual ISO - might consider this in the future - but still very surprised at how high an ISO the camera was selecting.
I've noticed that the Canon and Nikon large(r) sensor cameras do choose a higher ISO than would be expected, and I believe it's to keep a faster shutter speed to reduce any loss of shaprness. The Stylus 1 has a much smaller sensor, so I would expect that a lower ISO would be chosen to keep a better Image Quality (IQ). Since the larger sensors can handle the higher ISO without a lot of the typical noise for smaller sensors, Canon probably went for the higher ISO since most G7X users are not going to mount on tripods.
As far as the EM-10, I guess it would depend on what lens you are using and how fast it is as to what ISO gets selected by the camera. As you had noted, I would probably select an ISO and let the camera deal with the shutter speed. One question I didn't ask is if you are using Auto White Balance or setting the white balance to flash. I get much better results with the white balance set to flash and get more of the expected results.
! - Why would Canon (or Nikon) expect people to use a tripod when they are using a flash and therefore want higher ISO's for higher shutter speeds? And the shots I was referring to all were taken - the ones where I used the flash - at 1/60, not exactly a fast shutter speed considering the zoom range of the camera tops out at 100mm equivalent.
2 - But on the EM10 I was seeing AUTO ISO choose 200 almost regardless of the lens (whether a slower zoom or a fast prime) in the same type of lighting as I had at the party.
Just seemed to me unnecessary for the camera to select a much higher shutter speed than is necessary if you are forcing the camera to utilize the flash.
PS - no, I have only recently gotten the camera and it was set for Auto White Balance - and was very happy with the overall results, just surprised at the choice of ISO.
I think it comes down to Canon (and Nikon) lagging a little behind the others in sensor technology when it comes to low light capabilities. Since the other camera companies are not as big as Canon, my personal opinion is that the smaller companies are looking for a competitive edge to attract new customers, while Canon remains satisfied with a steady customer base that is apparently content with the status quo. As a comparison, just look how long it took Canon to compete with Sony's RX100 series cameras. The G7X is more like the RX100 mkII than the RX100 mkIII. The G7X is very capable, but yet it still lags behind the Sony with sensor technology. That's not to say the G7X is not a good camera, it is a very nice camera that performs well. But the old school way of thinking is that a tripod is used when doing flash photography, and Canon still has a lot of old school thinking with their engineering. Plus it costs more money to have that newer technology, and the price point for the Sony is much higher than the G7X, so there has to be a trade off somewhere. Just my opinion, and I still love my Canon cameras, all three of them.