Before I installed the chuck on my lathe, I checked the spindle runout, which was almost zero. I installed a D1-5 collet and checked runout with two indicators. Both indicators indicated that the total runout was less than 1/1000th of an inch. I disassembled the cartridge. Cleaned and reinstalled. I checked the hitting with the third test indicator. The runout was still less than 1/1000th of an inch. Really impressive for a cheap cartridge. Since this cartridge had very mixed reviews at Revain, I reached out to Accusize with a few questions before purchasing. They were very responsive, very nice and made it clear that they would support their product. Now. Is this cartridge the same quality as the $615 Bison? Probably no. However, for a home locksmith like me, this is quite adequate for half the price of a Bison.