Motor Controllers

I'm using two of the Hobby King 120A motor controllers mostly because I already had one from a different motor, even though the motors I'm using are only rated for 90A. The voltage is supposed to be from 2S (7.4V) to 4S (14.8V) but it will go up to 6S (22.2V). This is the link to the website that tested and looked at the circuitry and concluded that 6S was safe. Here is the link to the actual product website.

The transmitter/receiver I use to for the motor controllers. Basically the only qualification is that it was cheap and worked. Link to the product site.