Do u think a drop or 2 of glue may make them stay in place? I guess u would need to sacrifice 1 to make sure the glue and zinger material is compatibleSimplicity and structural integrity. These VPA's are machined from solid stock so there's no aluminum ferrule that may more easily bend or break. As far as the Zinger's, no I just put them on like a week ago but they seem to control these broadheads great. They are pretty tough to put on at first until you get your system down after that, they are very easy to work with. When you order them you have to specify the outside diameter of the shaft you will be using and the brand and category of shaft so they can make them custom to the bare shaft you're using. They don't move once installed but if you hit them with another arrow they will move up slightly but just move it back. I marked my shaft with a silver sharpie so I know where its position on my shaft was. Also, I had to install them to be 1.5" from the end of the shaft so they didn't stick into my cheek at full draw. I really like them so far. The only downside I can see is that if you do happen to hit one with another arrow, you have to throw away the whole thing but that is the only issue I see. I have the Z3's with a 3 degree left helical. I also ordered right helicals and one set of the Z4 with Right Helicals. So far the lefts are working fine for me.