yeah, for the most part I would agree. If mfg's weren't so eager to over rate their packs, then no there should be no difference ideally. In the real world you will probably notice a difference though. The better the 10C pack you have the smaller the difference would be. Of course though if you are running a battery pack up within 10% of its max cont rating, it's not going to last as many cycles as the 20C pack that you are running about 45% of its rating.