That experience with ‘bad’ cells is a compelling argument for having an analyzing charger vs something like the Xtar that only measures charge capacity. That, and the ability to program it, let it run until it’s done, and get the results. Manually discharging to a ‘known’ low cut-off in a reliable fashion is certainly possible but is going to be far more of a pain and not very precise unless you are quite diligent.
I had an Xtar. Fine charger, but I sold it when I got the Lii-500. Costs about the same, about as easy to use, does more. I got the C4 to check it out and like it even better and it’s also in the same price range. I don’t see a compelling reason to have a Nitecore, Xtar, or similar instead of a decent analyzing charger unless it has some very specific charge qualities that you want/require.