They have been a lifesaver for me. The insert allows you to feed the wires through one at a time while holding all of the ones you've already fed through in place. From there, it's just slide the insert down until it's where you want it, snip the excess off, insert the whole thing into the connector as a unit and crimp. I've gotten to where I can terminate an RJ-45 now in about 5 minutes, maybe less, and that's from strip to crimp - easily half the time (if not less) that it used to require, and they just work, every time. I haven't had a single failed termination since I started using these things.