Ordered the first supposedly very nice Chinese cartridge, unfortunately the taper on the back was off the ground and didn't touch the spindle nose taper. was able to use a piece of tape as a spacer and get about 0.001" runout on the nose cone. The film clearly shows the lack of contact. My spindle end-of-stroke measured with an Interapid 0.0001" DTI on the taper is less than 0.0001". Sent it back and ordered a new one hoping it was an accident. The second came, same problem, slightly worse by half a thousand. Also returned. I suppose you could spend time hard machining the back of the cartridge until it matches the spindle taper and then regrind the R8 nose taper and get a decent cartridge, but you could also spend the extra coin and get a Bison, when you have time with something .