I just got a Nikon M-223 in 1-4x. I have it mounted but have not gone out to shoot yet. However, I can tell you its the best glass I've ever had on a rifle. I'm tempted to get their 2-8 for another AR I own.
Next, you will not have to remove the front sight or swap gas blocks above about 1.5x. You will not see a standard front AR sight through a magnified scope or optic. It disappears. On the rifle that I have my 1-4x on, I have a YHM flip down sight/gas block so I can use the 1x setting if I choose, but dialing in 2x, the sight (in the up position) disappears.
Oh, what sad times are these when passing ruffians can say Ni at will to old ladies. There is a pestilence upon this land, nothing is sacred. Even those who arrange and design shrubberies are under considerable economic stress in this period in history.