basically they are pretty much same quality battery but I am suggested by the manufacture to carry only the 15C continuous discharge rate batteries, not only to have more power but also the quality of the battery itself.

So with only 1usd more, you get 15C battery instead of 10C battery. Mega Power is awesome in power. I put it in my Blade CX and Lama 3 and every time i swift the thottle, you can feel the power to lift the heli is much stronger than stock one and the heli responds faster.

Steve