Environment !!
it still is a good way to get rid of plastic and other organic waste. but at what cost of energy is the problem. How much energy the process will need? will it be cost efficient? What is the cost to benefit ratio? Perhaps one day oil prices will be so high that it will make sense. since "plastic" is a generic term for a variety of materials of various chemical composition, what are the byproducts of the process? Especially liquids & gases.