[jhautz]

Another note. The charger I use is the FMA Cellpro 10S and while it charges it also measures the internal resistance of the cells. I get around 20% lower internal resistance reading from the zippy packs than I do with my enerland packs and the temps the Zippy come off the track at are also easily 10F degrees lower also. Just my observations.

Internal resistance is usually a measure of the cell quality. While I'm sure the measurements the charger takes are not 100% accurate, they should be a good relative measurement.