They have them on sale, and that is a great price!
I am using a smaller 1/4 AAA cell that weighs only 2.4 grams each (not 4 grams). The only difference is they are 80mah instead of 150 like above, but 80mah is still plenty to get you through 8 minutes. The old Sanyo's were only 50mah (same size).
So, I do not need to remove the red wire from my ESC that plugs into the servo? This is what is was told (so the receiver and servo is only powered by the rx pack instead)...