Hi Tom,

For the Speed 400 Zagi XS, a pack like the 3-cell [link=http://www.hobby-lobby.com/kokam.htm]FM15003[/link] Kokam 1500mAh may be a good fit. The dimensions are on the Hobby Lobby site so you can compare them to the 1800mAh folded pack from Trick RC.

For the Wattage CAP 232, use two of the Kokam packs mentioned above in parallel or the [link=http://www.hobby-lobby.com/thunderpower.htm]TP420032[/link] ThunderPower 3s2p 4200mAh pack.

Since the voltage will be higher than the normal stock packs, try to limit your use of full throttle to short bursts of 10-15 seconds during the first half of the flight.