I make the entire logs from whipped soap, never use it for decorating (Piping bag challenged
The fact that it floats is an interesting selling point and I also find that it cures faster than soap using the same recipe but other methods like HP or CP.
I love the soap cake but really love your cupcakes! That is something I am trying to tackle right now. I just can't keep the fluf in the frosting after adding the fragrance. So on my last batch I Just fragranced the cupcake part and left the icing part alone and it was much better!
Now if I can only learn some piping techniques...off to youtube!