I have only used them on rare occasion, so not familiar with the product.
...egg substitute products such as Egg Beaters brand, contain 99 percent egg whites. The other one percent comprises undefined “natural flavor,” coloring, spices, salt, onion powder, xanthan gum and guar gum. Many nutrients are added to make up for the ones lost from the yolk, so egg substitute will usually contain varying amounts of iron, zinc, folate, thiamin, riboflavin, vitamins A, E, B6 and B12, and have an equivalent amount of protein as whole eggs. While some brands, like Egg Beaters, contain no fat or cholesterol, others use vegetable oil as an ingredient, which adds to the fat content again—though the fat is largely unsaturated.