I tried both as an adult and like both on occasion. I cook with them more often than I use them as a spread though. Vegemite seems to have more and different vegetable flavors noticable. Marmite seems a little sweeter, like a savory nutella or hagelslag (sp?). I'll put either on toast with butter, but I like them a lot better in soups or stews. With thai fish sauce, for when you have a fever for more umame.
