I suspect I'll be on 56 for a very long time as well. I ran on nightlies for many, many years but that ended at 57. At a bare minimum, noScript must be shown to be fully and consistently functional. But I have quite a few other extensions that appear to have been dead ended - self-destructing cookies and session manager are just two.

I think mozilla failed to understand that extensions were the prime differentiator and that a faster Chrome is far down the list of requirements.