TFA Sweetener actually contains maltol as well as Sucralose (not chemically identical to ethyl maltol, but I think it has pretty similar properties in a mix.) A small amount of EM can help take the sharp edges off certain flavors like citruses, but it can also mute flavors, especially at high percentages. You want to be a bit careful with it, IMHO, because it's already present in a _lot_ of flavors (there's a fair bit in TFA Strawberry (Ripe) and it's, by percentage, the primary ingredient in RY4 Double. RY4 Double actually has more EM in it than TFA Cotton Candy.) So you can wind up with quite a lot if you stack a few flavors that are high in it.