The controlller is one of the best designed I've seen released with a system, with playstation being the other one that really impressed me.

The two buttons and the top action button are easy to remember, and the select and run buttons are very nice, but seem a bit of a rip off of the PC Engine Controller design.

The cord is intolerably short. However as you'll see on the internal view, there's no internal chip for the controller, and you can use normal genesis extension cords with some minor modifications.

As you can see at the right, the control pad has no chip, so you can easily make your own arcade sticks with a bit of reverse engineering.