Vermont American makes a product called a "dimpler" of all things, it is a drywall screw drive for your power drill or cordless drilldriver. For about $10, you get a clutch that stops power to the driver tip the second the head of the screw bottoms out on the board, just like the pros do it.
They can be hard to find, but dilligence will pay off. I love mine!
On the other hand, DeWalt makes a nice drywall gun for about $100.
Good luck, and listen to Henry. He knows his stuff!