@JeffMoris It depends on the size of the motor - but you'll probably be best with an ESC from a hobby shop. Since it's an R/C car and single motor, the cheap ESC's that are use in R/C's take a servo PWM signal - which is compatible with EZ-B :)

I have an ESC in another R/C car. It's a Twin Detonator 4WD truck made by Tamiya. The ESC is Tamiiya TEU-103K. To make the truck run in reverse, I have to stop the truck, let go of the throttle stick, and move stick back again. I may need another ESC that doesn't have this feature but how do I find out if the ESC has this feature or not before buying it? The truck has two motors that's are similar to RS540S. The other R/C car has smaller motor.

The ESC will be labeled with reverse functionality.

I want an ESC that lets me move the robot from forward to reverse to forward without having to let go of the throttle stick. I saw a motor driver from Adafruit that lets me control DC motors, servos, and stepper motors but it's for Arduino board.

I dont think it can do that. Using ESC with reverse you need to go thru the brakeing first then reverse. If you would go from forward to reverse with out lowering the throttle you would end up striping or damage the gears. I dont have hands on with working with ESC with reverse. I just got my EZ kit last night and will be looking into this more as i progress.

http://www.robotmarketplace.com/products/images/0-BB-0309.pdf

Will this ESC work?

From this line describing it "Motor brake on neutral signal and direction change. Helps protect gears from over stress."

Sound like it would go right to reverse without a combination of movements needed. I will let someone who worked with ESC with reverse chime in.

I use mostly turning escs the turnigy trackstar series is good and cheap and is programmable (make sure to buy programming card) hobbyking us warehouse should have these for Cheap!