Does anyone here have much to do with these batteries?

These are the LiFePO4 cells that are in new(ish) powertools and what the shorai and such are made of.
As far as I can tell one Chinese company has it sown up but there are many knock offs that are almost the same. Thanks China...

Has anyone used these much apart from the branded versions?

If so, what is the main difference with the "B" or pirate cells?