ORIGINAL: RocketRob
The A123 cells are big and heavy and small capacity (for the size/weight). Other than charge shelf life and charge rate why not use a AA 2400-2600 pack?
The main benefit of these cells is the discharge rate, but isn't that wasted on a rx[:-]
You have to watch the ultra-hi capacity NiMH packs, some of them have a *very* high internal resistance.
It also pays to remember that the A123s can be recharged in a very short space of time (typically 10 minutes if you're flying them down to half) so you don't need the same capacity as you do with NiMH. When I want to fly the whole day I just throw mine on charge while I have a coffee or bite to eat at lunch-time and then I'm good to go again.
And two 1350mAH LiFePO4 cells weight a *lot* less than five AA cells.