Yep, the S100 in theory is better than the S110 due to being able to sync gpstime. Unfortunately the clock sync with the S100 internal clock is not accurate, meaning each time you fly you must work out a new offset (to use the KAP script logs to get the shutter release time).
Under good conditions it is possible to achieve geotags of 3-4cm xyz precision using the method I described in the post linked above. But the workflow is a bit time consuming. And there are better cameras for the application, the S100 and similar cameras need good vibration isolation, and high shutter speeds (at least 1/1250, preferably 1/1600) to get shapr images. Even so there are always a few blurred shots. Not a problem with an A6000…
I have a couple of the Tuffwing shutter sync cables waiting to go into my S100 machine, which is back in use now with a dual S100 setup, one coverted to NIR-G-B with the Event38 filter. So it will log one camera to the Reach, and one to the Pixhawk (though logging all to Reach would be better - feature request to add extra feedback pin options?).
I’m pretty sure the red-eye led/shutter sync method will provide more consistent results in any case, for the red-eye reduction to work correctly the control on the led firing must be quite precise.