I'd be very interested at a $1000 price point. Working on big rigs, tractors, etc in farm shops, this would be a sweet piece.
Even as a professional, I could see this being valuable. When I was wrenching, I'd often have a car on both hoists, and still have misc. jobs going in a flat stall. It would really be sweet if it would go high enough to use as a topside creeper. Sell it on tool trucks, and offer upgrade accessories, like lights, "Third hand outriggers", bigger tires, mp3 players, etc, and it would sell well, even at double the price, IMO.