Im a newbie but have tried both...wilton fondant is gross...I personally dont like it for anything but maybe making small accents...Satin Ice tastes sweet and sugary, which isnt bad. Its also a lot easier to work with!!!!
I used the Satin Ice White/Buttercream fondant for the first time today. It was a DEFINITE improvement over wilton. IMO people will still prefer buttercream but if you need to use fondant definetely buy Satin Ice instead over Wilton.
If I'd known physics and color mixing were going to be on the final exam I might have paid more attention in school!