Dear Raul, I owned both EPA 100 and speak from my own experience. They
are not suitable for MC carts. To put it otherwise ruby or sapphire bearings can't
support the needed counter weights. In this context I mentioned Ikeda-san .
I hope Albertporter will explain Breur bearings. My guess is that the bearings he used explain why he refused to provide his customers with extre weights. Very Interesting to know that you are more knowledgaable than Ikeda san.