Ive been playing around with em, set a few into a piece of scrap sheet just to see how they work. Drilling the correct hole size is crucial to them holding. But once theyre crimped, there is no chance of ever pulling it through the hole. You can get them in both AL & steel. The AL ones are very easy to crimp, easier than using a pop rivet gun, altho you have to be careful because you can actually rip the threads out of them with the tool while crimping it. The steel ones are harder to crimp of course, but once done, its there forever. The 8-32 riv-nuts im using have ~ 1/4" of thread, so theyll hold far better than i need for a set of fender flares.
This is the crimper i bought:
Comes with a bunch of dies & riv-nits, but not 8-32; that i bought separate (also from amazon)
Attached is a pic of the backside of one of the 8-32 nuts crimped. Looks good once done. When youre using them, youd think you were threading a screw into a tapped hole not an insert. I love em, im gonna end up using these things everywhere