This is my servo of choice for any 50 to 90 size helicopter. The JR DS8717 is the fastest, most powerful servo on the market capable of super fast speeds and rediculous amounts of torque!

• Fastest servo on the market. The speed of this servo is .07 Sec/60 Degrees at 6 volts. However, this servo can handle a straight 2 cell lipo setup (8.4 volts) and it shines at the voltage as its speed increases to approx. .05 Sec/60 Degrees.
• More torque than any other helicopter servo. This servo produces 196 oz/in of torque at 6 volts. When plugged into a 2 cell lipo without a regulator, the torque increases to approx. 220 oz/in.
• These servos have metal gears, which is a good advantage as gear replacement is usually not required after a crash.

These servos are competitively priced. They retail for about the same as many other high end servos. Please visit http://www.horizonhobby.com/ for prices and availability.