The standard shimano bearings are rated using a Japanese system, and are typically JIS4 (which I believe is somewhere in the range ABEC3-4). The black A-RB Shimano bearings are JIS4 and, IMHO, are just as good as the ABEC5 and ABEC7 BOCAs. Personally, I did not notice much of a difference in casting distance between all the bearings for lures > 7g, provided the stock bearings are cleaned with acetone and lightly lubed with a low viscosity oil (YRF or Friction Zero). Flinging the really light stuff is where the differences appear. Japanese ZPI bearings are also super bearings - very quiet and easy to clean/lube as they have no shields.