ORIGINAL: Rodney
I have been using Sanyo Eneloops on three different .40/.60 sized planes with no problems. Four standard sized servos, 2000mah Eneloops. It is true that Eneloops have a slightly higher internal impedance than NiCads of similar size but not that much different. If you are truly worried about that and your plane can stand the extra weight, just parallel two packs as that will half the equivalent internal impedance and give you twice the mah capacity.
+1
that's what I do in four planes 2 size 40 and 2 sixty size only one has parallel packs
so great to charge plane an weeks later grab an go typ recharge with about 530 mAH back ( 4 to 5 10 min flites )
Rich