It IS WMS. It is just amylopectin, it's like eating a plants "glycogen."
I have never used it because I dont see the real benefit over any other form of carbs, I dont use dextrose either. The only benefit is that is allows more water to stay in your stomach so gastric emptying time is increased allowing it to get into the blood faster than other carbs. But just drink a lot of water like we all should anyways and you can save yourself some money and use oats.