I chose lipo simply because of my prior experience with them.  1 of the first in the Ohio area to use lipo in electric powered aircraft.  Been using them for almost 15 years.  I remember well, the 3c discharge rate 1080 mA packs.  Had to charge them at 1C rate.  It was nothing for a 7 minute flight and an 80 minute recharge.
There have been many advancements in technology with battery builds, chargers, now parallel charging.
I have done everything wrong that you can do with lipo, with the exception of plugging one in backwards, to create a failure.  Have I seen performance degrade, yup.  But still showed an 80% recharge capacity.  I must have 30 packs that need to be disposed of.  But I want to have fun doing that.  I don't believe in keeping lipo in a container for storage.  There is no potential for incineration.  It is only under a charge/discharging condition.  I have said this before.........  Do what you feel is necessary to store them and charge them.  What I do works wonderfully for me, but may not work for anyone else.  I charge and store packs in all my aircraft.  I do balance charge each charge now.  I never used to, until I checked the balance of my packs 1 day.
When it comes to new, larger cell/capacity packs........ Beat the crap out of them for approx 50% capacity.  Then recharge them, and do it again and again for a few flights.  IRs will come down low and will give you the power you need, easier under a higher load condition, much like in an E heli.
I fly lipo because I don't like A123 packs.  Have I used 123s? Yup.  Built my own 2S2P 4600 rx packs.  1 pack was perfect, 4600 ma. Other pack was only 2300.  Had 2 dead cells after I built the packs.  If I were new, I would try each, and see which I liked best.
All my aircraft are outfitted much similar.....  Dual 3600 Glacier 2S lipo Rx packs hooked into a JR DMSS PowerSafe Rx and soft switch.  I will use a regulator on the ignition system that is rated at 6V.  A castle BEC is my choice there, just the little 10A.  Unless I decide on a WrongWay step down diode.
I know, a bit long winded.........  But drag racing is on now and it is time to watch some 4 wide quails and grab a pain pill.