I was doing like 6 or more. Depending on how many planes I would bring out. When it was just the 28% then yes it was easily 6 or more. There is no perfect setup no matter how you look at it. There will always be a compromise somewhere or at the very least one weak link in the chain.

Most 4 cell lion packs are redundant within themselves; if a set of cells fails the other 2 should take over. I guess if you wanted to get a 4 cell pack with two sets of leads..ect.

If you setup your plane correctly and have your RX isolated from vibration I dont see what the problem could be. Get a good reg or a setup where if the switch fails it does so in the on position. The 4 cell Lions will put out more amps then a 2 cell pack and more than likely you wont fully drain a 4 cell pack.

Lions like to only be discharged about 75% of their full charge regardless of setup. Keep this in mind and your battery will have a long life.

Tom designed this plane to be light and fly light. If you add a lot of things which are not needed you will take away from its design.
The same can be said with most planes.