[chrisguyw]

MR Slotcar (in Hallam just south of Melbourne ) sell Difalco controllers, which over the last 30+ years have been the most popular controllers worldwide for the type of motors you will likely be running. There are several options, worth contacting them for info.

Controller technology has certainly changed with "electronic" controllers replacing resistor based units..............in very basic terms, the electronic controllers have a variable sensitivity pot/knob  built in which (again in very simple terms), acts like having adjustable "ohm" settings  in the controller, to work with a variety of motors.

Cheers
Chris Walker