Bigmatt I like the TKO but next time I want to try 1 of them new Protec bearings steel for the front its sealed on 1 side and has some wierd new kind of partial seal that they say let the bearing spin much more freely and they are only $5 for the front at A-main and for the rear I price permitting want to try the 100% ceramic rear if not TKO. I have fr and rear TKO's in my 5 port and they I have to say it seems like the mill idles much better with them. The stock bearings on GO mills are some of the best in the buisness mind you. I just like to try new stuff. When I swapped rod pin and clips I did the TKO's. My stock bearings were fine. Still have them. They are Italian made so right there tells you they are good.