Im going to go with you on the 6000 spec. Its an industry standard and it would ridiculous for them to have standard with variation.
8 bearings coming my way, 4 for me, 4 for my lady.
now that they are ordered. Is there a noticable difference?
I went from suzue basics, to IRO and that was a world of a difference. Recently I noticed these(iro) were'nt moving as freely as they were from day one, and even after cleaning them they did not impress me. Back in the skateboading days i used to buy bearings every 6 months or so, i wouldnt buy the best since they were taking a beating anyway, but even those would spin like crazy. I am under the impression that these, provided they are cared for, will last considerably longer.