18650's and their quirks

[J57ltr]

What gets me is that I can pull almost full capacity out of them but only at pretty low amperages, but others I can get the same at higher amperages, all while having IR's that are very close.

What's even more odd is when I tested them as sets of cells 3P and 2P they all had the same discharge and charge times and mah, but seperate they are wildly different.