I also installed w10m right away after getting the phone before the New Year. It works great. I switched to it from Lumia 532, so I thought I would miss the glance screen, but l actually I don't. I just grab it, double tap or something, and I also see everything in an instant.
Those who upgrade. Some say that Lumia camera is still better than Windows camera, so if you want to keep it, after the hard reset on w10m turn of automatic updates in the Store, and don't update Lumia camera. I use Windows camera only, but I'm just saying.
Oh, and only do the hard reset right after getting w10m, that is the version 1511, and after that setup everything including calendar, and that don't do any hard reset after getting the 1607 version. No need for that, and you will avoid the calendar live tile issue.
Sent from mTalk on Windows 10 phone