The NECG sight is pretty well made. It clamps onto a Weaver style base. I bought one hoping I could use peeps, but that did not work out.
It has two draw backs for me. One the stem of the peep is used to lock the slide in place, and two the opening when the peep is removed is rectangular. Because of this one cannot use the sight minus the peep as a ghost ring.
Neither draw back would be a problem if you were able to clearly see through the peep. My eyes will no longer allow that.