I take casual snaps of people in daylight with fill flash a lot. I used to have an interchangeable lens camera (which is limited to roughly 1/200 sync speed) but I sold them all to switch to Fuji's X100 camera line because of its leaf shutter. The X100's leaf shuter allows you to sync at 1/1000s at f2. That's a 2- to 3-stop advantage over a focal plane shutter in the typical interchangeable lens camera so you can have a much smaller and portable flash and still have the same illuminating power.
I have both an original X100 and an X100F for this reason. Probably my favourite camera.
The X100F is interesting for having both a leaf shutter and an electronic shutter.
Also good for high speed flash are the old Nikon 6MP cameras. I have an old D70 somewhere that I've used for high speed sports portraits.
Apart from the small image size it's a great camera. You can sync from the hot shoe at any speed, although practically this is limited by the t.5 time of your flash gun. For a Nikon SB-800 and the sort of power I was using that was about SS 1/2000.
For anyone considering this, please note that if the flash is iTTL-compatible, you'll be limited to 1/500s. (This is because of the flash duration at full power of the Nikon iTTL flashes of the same vintage.) A "dumb" flash will sync at all speeds since the centre pin is live at all times and the flash doesn't talk to the camera through any other pins; your t0.5 and trigger become the limiting factors. (Many radio triggers will not work reliably above 1/500, and only a very few are usable above 1/1000. A shoe-mounted flash or a cable connection doesn't have a trigger-speed limitation as such.)
If only that 6MP sensor had a broader ISO range. If you're not shooting for the big print, 6MP goes a long way.
