Ok so I'm playing with my PowerLab 6 today and wanted to see the difference between my 2S Nanotech packs, 2S GensAce Packs and the 2S SMC 6570 I just got.
He who's name shall not be spoken

said to be careful with the internal resistance measurement on the PL6 but that it would be ok to use to compare packs under the same conditions. Well what I found is that the NanoTechs and GensAce give an IR just below 4 mOhm and the SMC is around 2.6 mOhm. Or something like 30% lower.
My understanding is lower is better...so I can't wait to get this thing on the track.
Still need to test my Throttleworx Shorties to see where they fall.