I use JR 700 ma battery's in my .40 size planes. They easily go 5 to 6 , ten minute flights.
On my .60 size planes , I use JR 1100 ma and get a lot more flights, maybe 9 or 10. I also loaded test before every flight , just a good habit.
I never charge my battery's unless I`ve pulled them down to their minimum charge under load. So far it has worked good for me., but I do agree , a battery cycler is the way to go.