Pedazo servos se ha marcado Align...
Os resumo las características rápidamente:
BL700H: servo para cíclico 550/600/700; 20Kg y 0.065 a 7.4v
BL750H: servo para cola 550/600/00: 7kg y 0.032 a 7.4v
Impresionantes... eso sí un pelín caros; andan por 145$ en las tiendas.
Las características completas son:
BL 700H High Voltage Brushless Servo HSL70001

Instruction:
●Utilizes brushless motor design for fast speed, high efficiency. And with the absence of brush wear, the longevity of servo is greatly increased.
●Supports 7.4v high voltage to provide optimal speed and torque performance of the brushless servo.
●Designed specifically for helicopters, with highest specifications on the market: 0.065sec/60°ultra fast speed and 20kg-cm monstrous torque, allowing helicopter to perform with faster and higher precision.
● Ultra high 12 bits signal resolution for excellent precision and smoothness.
●Hardened high strength superalloy gears that increase the lifetime.
●Aluminum alloy mid case construction for instantaneous heat dissipation, maintaining servo’s high efficiency.
● Supports both analog and digital control signals.
● Suitable for T-Rex 550/600/700 cyclic and rudder use.
Specification:
●Stall torque:15.0kg.cm(6.0V)
20.0kg.cm(7.4V)
●Motion speed:0.085sec/60°(6.0V)
0.065sec/60°(7.4V)
●Rating voltage:DC 4.8-7.4V
●Temperature range:-20°C至+60°C
●Dimension:40.3 x 20.1 x 38.7mm
●Weight:69g
http://www.align.com.tw/shop/product_info.php?cPath=22_29&products_id=4382BL 750H High Voltage Brushless Servo HSL75001

Instruction:
● Rudder servo with .0.032sec/60° ultra high speed response, pushing the extreme.
● Utilizes brushless motor design for fast speed, high efficiency. And with the absence of brush wear, the longevity of servo is greatly increased.
● Supports 7.4v high voltage to provide optimal speed and torque performance of the brushless servo.
● Designed specifically for helicopters, with highest specifications on the market: 0.032sec/60°ultra fast speed and 7kg-cm monstrous torque, allowing helicopter to perform with faster and higher precision.
● Ultra high 12 bits signal resolution for excellent precision and smoothness.
● Hardened high strength superalloy gears that increase the lifetime.
● Aluminum alloy mid case construction for instantaneous heat dissipation, maintaining servo’s high efficiency.
● Supports both analog and digital control signals.
● Suitable for T-Rex 550/600/700 rudder use.
Specification:
●Stall torque:5.0kg.cm(6.0V)
7.0kg.cm(7.4V)
●Motion speed:0.045sec/60°(6.0V)
0.032sec/60°(7.4V)
●Rating voltage:DC 4.8-7.4V
●Temperature range:-20°C~+60°C
●Dimension:40.3 x 20.1 x 38.7mm
●Weight:66g
http://www.align.com.tw/shop/product_info.php?cPath=22_29&products_id=4381