Yeah that's another variable. If you are drawing current near the max level of a pack the voltage drops more resulting in less watts (or similar) but at a higher current draw yeilding less performance (or similar) and lower flight times. Because of this you usually end up at higher throttle to get adequate performance... thus lower voltage/higher amp draw... etc.

A pack that is optimally drawn on doesn't drop voltage as much providing more watts at less amps. So you fly with a little less throttle. The combination of these two factors lead to longer flight times. Of course we often splurge inthe extra power and end up with the same flighttimes, but at better performance.

Did I word all that right?

Anywho... I think ThunderPower would have been my first place to search for a balancer as I usually choose their packs...