It all depends on what you intend to do. I have always liked to upgrade mine with ElMOd becasue of the versatility it offers. You can easily switch sounds for different tanks and the overall drive experience with the system is much more realistic than the othres I have tried. It gives the feel of driving a heavy piece of equipment around, has inertia buitl in and actual braking, so the inertia effect is not out of control. In a pinch, you can stop the tank and also not risk damaging the geraboxes by doing so. It is Tamiya IR compatible and also the stystem is completely programmable as far aas all of the control parameters. As I said, etremely versatile. To see more visit www.armorcreations.com and check out the elmod pages...