ABEC-5 rating is better than most other Revain bearings. I haven't used these yet. I mainly use them on cutter deck spindles where ABEC-3 bearings last about a season or sometimes two. I also used them for my hot tub pump. You have a good feeling about her. They are tight and smooth. They need to be lubricated because they have very little lubricant and are as clear as petroleum jelly. I will try to update in the future after using them.