I have tried twice to install this update on a good NBN connection. I left it for 24 hours the first time, and for 5.5 hours the second time. Both times the installation stuck on 0% for a really long time, and eventually hung at 84% with the normal warning not to turn the computer off.
It seems the main way to avoid an installation attempt is to leave the computer on 24/7, and to try to keep putting off the forced update for as long as you can. Since powering the computer down when it's spinning on a blue screen warning you not to turn the computer off, followed by an 'Attempting to recover...' message when you're inevitably forced to power down in order to get a workable computer back isn't reassuring, I was hoping for a workaround.
I think there is something wrong, and I'm waiting watching for solutions, Microsoft.