Specifications:

20amp Speed Controller
Nixx: 5-12NC
Lipo: 2-4
Weight: 20g
Bec Output: 5V/2A
Dimension (W*L*H) : 23*33*6
Programmable: YES

Specifications:

Cont Current: 18A
Burst Current: 22A
BEC Mode: Linear
BEC : 5v / 2A (3A burst)
Lipo Cells: 2-4
NiMH : 5-15
Weight: 27g
Size: 45x24x11mm

ESCs from HW come under many names . You should be familiar with some - Emax, Turnigy, OEM RC, EMGC - but don't be fooled they are the same. You don't need to pay more. They are also the best - simple as that.

Specifications:

32 x 24 x 7 mm , weighs 25 gram Constant current 20A Max 25A <10s
Li-Poly 2-3 cells; Ni-MH 4-10 cells Auto Detect
Brake On/Off
BEC: 2A

Specifications:

23.5 x 15.7 x 6.1 mm , weighs 17 gram
Constant current 18A Max 20A
Li-Poly 2-3 cells; Ni-MH 4-10 cells Auto Detect
BEC: 1A
Auto shut down without signal.
Auto Low battery Slow down at 3.0V/Lipo, cut-off at 2.9V/Lipo
Limited programmability easy to use.
Auto Low battery Slow down at 3.0V/Lipo, cut-off at 2.9V/Lipo

This is a good entry level speed controller and is on par with Towerproand other hyped up budget brands.

Specifications:

Cont Current: 18A
Burst Current: 22A
BEC Mode: Linear
BEC : 5v / 2A
Lipo Cells: 2-4
NiMH : 5-12
Weight: 19g
Size: 24x45x11mm