I use a Hyperion 2100 mAh LiFePo4 pack in my 10CHP. LiFePo4 is a much better chemistry for transmitter use than LiPo. Thermal runaway is impossible, the cells can handle far more abuse, and cycle-life is higher. Plus, the 3.3V/cell nominal voltage means that a 3s pack is perfect for transmitters that use 8-cell NiCad or NiMH packs, and the 2.8V/cell minimum voltage works well with non-adjustable tx battery alarms. Also - the Hyp tx packs have a built-in circuit so that you can still use the NiCad/NiMH wall-wart to charge the pack in the tx if your regular charger doesn't support LiFePo4.
I see no downside here for those with 9.6V transmitters.