I'm unfamiliar with the TZ business, but the Enduron line came from roughly a year ago when General Dynamics totally rebuilt their plant in Quebec(formerly IMR). The "Copper Cleaners" are French tech from about 1900, you can read about it in Hatchers Notebook. Originally it was only Tin Compounds, General Dynamics has added a series of Bismuth compounds as well, and tweeked the amounts. The tin compounds for cleaners has been in 760/414/748 for essentially ever; Olin just didn't promote it well. Temp sensitivity works, just have to know what a thing is designed around. One of the things that many don't know, is that when a powder tries to compensate for heat soak in the primer, the powders burning rate actually speeds-up, or slows somewhat. To see this on a chrono it needs to be good, and have someone shoot through it frequently. Can get a bit interesting if you are loading extruded by weight instead of volume, makes the movements difficult to track without some pressure equipment. For the average Joe, do a simple heat soak test. So shoot enough quick rounds to get the barrel good and toasty, through the chrono. Then follow up five rounds, with various amounts of time sitting in that hot chamber; you can see it on the chrono then. Kind of interesting.