me with GoPro stereo-rig 3D

If you can do a good sync, it should be reasonable. What I've done on non-sync cameras is to make a loud noise, like a clap after I press both buttons. All noise typically has a peak that can be easily synced in a good editing program. However, after I discovered the Gopro 3+ setup, I have used only that.

Here is a simple 3D printed frame I had made for me (my design) along with an adjusted sync cable that I patched (open it up and cut a slot in in the other side and run the wire through it and patch the original side). This extends the cable very easily without damage.

Simple dual wide/narrow frame with tripod mount and back mounted cameras-lock piece.

Two 3+ gopro cameras set to 2.7k Narrow for best reasonable image. Two sync cables, one modified for wide separation.

Wide separation mount. Note two control holes. Using modified sync cable.

Front view of wide separation mount.

Basically, just flip case left to right and push in cameras from the other side and use a regular cable, though a modified cable can work. The back clip is mounted to keep cameras from sliding forward or backward in the mount causing alignment issues. Regardless, due to anomalies in 3D printing, you will still need a good post processing editor (ie. Edius) to align properly.

My experience is that although the wide separation creates more depth it also creates miniaturization of the image. And actually, due to the wide angle of the lens, the original separation appears more correct and the depth is really ok.

I used this extensively on my trip to Tanzania, Africa in 2016.

Here I'm doing the jumping dance with the Masai tribal women. You can see the still camera (Panasonic ZS100) and the Gopro cameras case, plus it has a strap holder on each side. Very easy to carry around.