You might want to try running the upgrade using the
MCT the USB that is created has all but one update included. I'm seeing on the Windows 10 Forum a lot of people are have better success that way.
I would also recommend that you use
Macrium Reflect Free or some other imaging software to create a Image of your Disk before starting the upgrade. Restoring an Images is fare faster than rolling back and less chance of errors. At least you would have a back up in case the install doesn't go well or rolling back fails somehow.
G752VY-DH72 Win 10 Pro
512 GB M.2 Samsung 960 Pro
1 TB Samsung 850 pro 2.5 format
980m GTX 4 GB
32GB DDR 4 Standard RAM
Z97 PRO WiFi I7 4790K
Windows 10 Pro
Z97 -A
Windows 10 Pro