I need to make the cake topper, I'm not sure which would be better...(I've always just used fondant with some gumpaste mixed in) I need to make a 60th and place rhinestones on it. would you use fondant or Royal icing? Someone suggested RI but I'm afraid the rhinestones may make so its not strong enough... any suggestions?

Make it in multiple steps. Make the base in Royal icing and let it dry. Then do the next layer with more royal icing and place the rinestones on it. Thisway you have the strength and don't have to worry about the rinststones going through the royal and making it fragil