It's my personel view that FMA won't be successful selling LiPo packs to C50 Hacker pattern flyers until attention is paid to battery pack weight. A Hacker C50 spinning a 22 x 12 APC on a windy day can pull in the area of 4400 ma from a pack. The only current Kokam pack with sufficient capacity to meet that kind of a need is the 5S2p 6400 pack, two of which (in series) weigh nearly 4 lbs.! The next lower size pack is the 5S2P 4000 which, while it weighs only 38.4 oz, does not have sufficient capacity. The 5S1P 3200 is not even a player. I have not seen the weight of a 4800 10S pack; however, a 2S1P 4800 pack weighs 115 grams. From that, I would estimate that the 4800 cell used in a 10S string would be close in weight to the TP5300. But....why would I buy a Kokam 4800 if I could get a 5300 mah TP pack at the same weight. In addition the TP 5300 has been establishing a very good performance record. Weight Mr. Marks....I can't buy your LiPos for use in my pattern C50 powered pattern aircraft until I can obtain something that will provide sufficient capacity to make it through upper class patterns with sufficient reserve to support a margin of safety and good battery longevity, while keeping my aircraft under the competition weight limit.