Interesting discussion.   

I feel you guys may be the last of the builder's era.  If local clubs are any indication of the future, it is not bright.  I belong to 2 clubs.  (It was 3 clubs, but 1 closed Monday.)  The biggest club is about 150 members.  Out of that, there is maybe 3 builders.   I have pushed people to build, by giving them the kit and parts to make it.  One person, a doctor took the offer and built (with a lot of help) a House of Balsa P51, 60 size.  He converted it to electric.  It took about a year. He was successful and I flew it for him.   He was very, very proud of his accomplishment.  I have given kits to 3 other people and none of those ever started the kit.   The reason is they give is WHY?  Why spend the time doing all that work, when they can buy a plane ready to fly and go fly.   I explain that building and fly are two very different tasks.   Building gives one a deep satisfaction and pride when they fly a plane they made.  If you never built one, you cannot know that.  Convincing people to try it, is nearly impossible.   They make stupid excuses that programming the receiver and transmitter for their new FOAM ARF is more difficult than building.  Bull Hockey!!!   I know programming and it does give satisfaction, but not what you get building.   And, as I explain to them, that very ardent task of programming cheats them out of reallyl learning to fly, because they are programming SAFE receivers that virtually fly the plane for them. 

What does it mean to us?  It means the hobby as we love it,  is dying.  Eventually, you will have to confront people like I describe and their demand to fly ARFs or you won't have many competitors.   

I still think you guys that are here now, should consider, just for the hell of it, changing your rules as Sparky suggests.  That would truly get the most out of you, who are the last of the best.   

or see Igor about a prop.

Unfortunately it is time to approach the finance committee.

Ken

Folks say you should reduce the low-voltage cutoff in the ESC.  Voltage drops more during a flight with a Li-Ion battery than with a LiPo.

Exactly, that is also reason why the LiIon combo needs MORE voltage head room than compared LiPo. Wheather LiIon can replace the LiPo in particular setup is question of that volatge head room. Motor will need pull hard when pulling nose up, so lower voltage can limit that boost. If there is enough head room it will be covered, if there is not enough, especially on end of the flight, it will loose speed. This problem is magnified by string sensitivity  of active timers. Solution is motor with more KV but it will also need more amperes.

In any case, LiIon 6s battery has end voltage like 5S Lipo battery, so it will always run at lower efficiency, fortunately it has more capacity.

or see Igor about a prop.

What Keith said!