KO Propo 30100 "RSx Response H.C."
Specifications:
Voltage: 6V or 7.4V
Torque:
@6V: 200.1 oz-in (14.5 Kg-cm)
@7.4V: 242.9 oz-in (17.6 Kg-cm)
Speed:
@6V: 0.07 S @ 60°
@7.4V: 0.06 S @ 60°
Bearings: Dual
Lead Connector: Gold plated
Gears: Full metal
Weight: 70.5g
Size: 41×37.5×20mm

and

KO Propo 30101 "RSx Power H.C."
Specifications:
Voltage: 6V or 7.4V
Torque:
@6V: 362.9 oz-in (26.3 Kg-cm)
@7.4V: 436.1 oz-in (31.6 Kg-cm)
Speed:
@6V: 0.13 S @ 60°
@7.4V: 0.11 S @ 60°
Bearings: Dual
Lead Connector: Gold plated
Gears: Full metal
Weight: 70.5g
Size: 41×37.5×20mm

i have heard nothing but amazing things from the people that run those servos, expensive yes.. but amazing servos