I have set my camera up to use manual settings for aperture and shutter speed while setting my ISO to automatic, as per the instructions on a couple of Youtube videos, as I fancy trying it out. I'm presuming it will be a question of getting used to it, similar to when I started to use back button focussing.
Anyone use this method of exposure and how is it for you?
I use it for birds/wildlife (and on my very occasional street photography).
I set the aperture near to wide open, and then choose a shutter speed to match the action. I can see the ISO in the viewfinder and try to choose the best shutter speed while also watching what is happening to the ISO. If things are happening fast, I just adjust the shutter speed and ignore what the ISO is doing.
If a flying bird ends up perching in front of me, after grabbing a few shots in the air, I can take the time to choose a longer shutter speed and bring the ISO down.
As others have also said I use the highlight weighted matrix metering on my Nikon D500, and almost permanently have a +0.7 exposure compensation dialled in. But I often add more than this. The Nikon highlight weighting seems to make very little differences if there are only a few high lit areas, but becomes stronger as the proportion of bright areas increase.
I feel (not tested it yet) that although the highlight weighting seems to work extremely well, it's also easy to badly underexpose the shadow side of backlit birds. Which is less of an issue with ISO invariant sensors (400 ISO and above on the D500) and software like DXO, than it once was. However, I still add some exposure compensation in backlit circumstances. I chimp the histogram to help judge this, or just add 1 to 2 stops.
I have the Nikon function control option "release button to use dial" set to "on" (f6 on a D750), so I don't need to hold the compensation button down while trying to adjust the compensation. I found this makes adjusting exposure compensation much easier than the Nikon default.
For landscape I use fixed ISO and manual aperture and shutter speed. When you have the time. I find this the most straight forward approach and only go above base ISO when there is subject movement (flowers blowing in the wind etc), and I need a higher shutter speed.
But for fast action type photography, I find auto ISO invaluable. I can "set and forget it" for when taking time to make any adjustment might lose me a shot, but equally I still have quick access to fully controlling the choice of ISO, shutter speed and aperture, when time allows.