Has anyone installed the current Fast Ring 14946.1000 on their Lumia 950 successfully? After the update installed (spinning gears) and started its reboot, my phone was stuck at the Windows 10 blue logo and never progressed. I tried letting it sit there for 30 minutes. I eventually pulled the battery, but could never get it to finish. So, I did a physical hard reset, which appeared to work. But then I needed to re-enable Insider Preview settings, which requires a reboot, and was greeted by the very same problem.
So, I used the Windows Device Recovery Tool to go back to the original firmware. I'm hesitant to go back to the Fast Ring right now without others confirming they have successfully installed it.