I have been using the insider program (Fast Ring) for the last couple of months, since I am sure that when Windows 10 Mobile is released Verizon will not push the update for another couple of months at the earliest.
Since I started using the Win 10 Mobile on my Icon,the updates for me have progressively improved the operation of the phone. Currently release.71 has been good, my apps do not crash but I do have an occasional loss of LTE data which forces a restart. Most of the time the reset works, but once in awhile the screen locks up and I have to do a hard reset. I feel it Win 10 Mobile needs a little more polish but is a big improvement from the earlier releases. My battery life is not a whole lot different from when I had Win 8.1 on my Icon.
My only other dilemma is deciding if I should get a 950 right now I do not feel I am getting a big improvement, all I lose is not having continuum and a higher resolution display.