The problem with the centering of the cartridge is worth everything else. I discovered the backlash of the cartridge immediately, drove into the store, they said that it would run in in two or three days. Used for two weeks, work is inconvenient. A hole in the wall begins with peeling of the plaster around, it moves out on the metal, it’s even useless to core. Without pre-drilling, you will not get to the intended point. A thin drill deepens quickly, but also not always accurately, and using one drill for drilling and the second for drilling is simply stupid. In a store of 4 bosses, everyone had a beating (to varying degrees), so I chose the one with the smallest one. Now I'm suffering.