I ran the SB version of these, so 1420-16 here. These were riding on a Hughes Engines sourced rocker arm shafts which had banana groves in them...ended up having a good amount of bluing on the shafts. The rocker arms never got hurt, but when you see colour like that you get worried (well, I did). Top end oiling was great, some on the forum suggested an issue between rocker arm and shaft material...leading to possible gauling.

For what it's worth, if you are buying new why not buy the bushed ones instead?

If I was buying today I would pick up the 1622-16 for the SB application.