In addition to the Ceinier unit, I currently have a cheap Chiappa 1911-22 and the old Colt style conversion unit. No doubt that the Colt unit is the premier act to be followed BUT. With the good Colt magazines now running upwards of the hundred dollar mark, it gets a bit scary supplying practice mags for a day on the range. I am not sure what is going on but the one company who currently makes a usable replacement mag for the Colt conversion unit, with a follower that should lock the gun open, grinds away the locking tab??? Be sure to always keep a tiny bit of Break-Free on the floating chamber, them do be a booger iffen you let them get locked up!