I help my friend who does Toyota's snow removal at the Georgetown, KY plant and they started using beet juice about 3 years ago. They do mix it with a salt brine solution. The beet juice runs around 15-20 cents a pounds. They use it on there test track and from the exit of the factory to the shipping yard. It works very well you can tell right to the spot it was placed.
The biggest pros I could see from it was it took at least 3-4 pushes of snow of the normal bine or salt rock before the snow or ice started to build back up. The stickier beet juice allowed more traction. Also the beet juice will work at a whole lot lower temperature then a normal treatment.
The only cons I see with it is the price, and messing with the nasty stuff.
In the shipping yard they use potassium which is junk in my opinion.