Here is post #11 from, RCU "Electric Pattern Aircraft" section - http://www.rcuniverse.com/forum/fb.asp?m=11466630 :
Silent-AV8R: It is not a question of me "thinking" that this is the case.And it is not at all about "HobbyKing" stuff -it just happens that they sell the Turnigy SK3 motors which are made by the SunRay Tech factory.
No, the issue is MUCH MUCH wider than HobbyKing, or Hacker or others. -It is about one single factory making the same exact motors for more than 25 different brand names.
We do know, without any doubt whatsoever, that Hacker, Hyperion-Z, OK Hobby Infinite and Turnigy SK3 motors are all made together at the Sunray Technology factory in Shenzhen, China.</p>

-And not only are these motor brands made at this Sunray factory. Many others are also made at this factory, including: Extreme Flight Torque, Shulman Aviation FURY, Gens Ace, Common-Sense-RC, LiPolice, Pelikan Foxy, Viper VA, Apache, Pilotage Nova-Line, MegaPower Taurus, Lipotech, Sonic Electric, BMI Models "Spitz" motors, Precision Aerobatics Thrust motors, Waypoint E-series motors, Boost motors (from Pichler -sold by Robotbirds in UK), JP E-Pro motors; ELE motors (now discontinued) -there are probably more than this, we just don't know about them yet ..

-That is precisely why all these motors have basically identical specs and completely identical performance
-Hacker motors are just the same as all the rest -they are totally IDENTICAL internally and in performance -and there is no earthly reason at all why we should pay 4 or 5 times as much for a Hacker or E-F Torque motor ..</p>

ALSO: We know that O.S. motors, and Futaba motors, are also made at this Sunray Tech factory.</p>

In addition to this, we now know that Sunray also make the ESC's for most of the same brands that they make brushless motors for. -This a relatively new finding.
see: http://www.rcuniverse.com/forum/fb.asp?m=11452486 post #43 onwards.</p>

We know for certain that Sunray make the following ESC's: Hacker X-Pro; Hyperion Titan; Extreme Flight Airboss; Common-Sense-RC; Sonic Electric; Gens Ace; OK Hobby Infinite; Shulman Aviation FURY ESC's; Apache; LiPolice; Pilotage Nova-Line; BMI Spitz standard ESC's; BMI Spitz data log ESC's; HDX Brushless 35A ESC; JP E-PRO ESC's; and also: ELE-RC "Advance" ESC's (now discontinued);</p>

In addition, Sunray Tech also make Turnigy dlux ESC's., and Turnigy Trust ESC's.
It is also very likely indeed that Sunray make Jeti ADVANCE and Jeti SPIN ESC's; see http://www.rcuniverse.com/forum/fb.asp?m=11463027
They may also make Precision Aerobatics Quantum ESC's (after all, they DO make PA Thrust motors ...)</p>

See: http://www.rcuniverse.com/forum/fb.asp?m=11465548(and also perhaps: http://www.rcuniverse.com/forum/fb.asp?m=11465908 )</p>