Okay here is the question:
what is the advantage/difference between crusting and non-crusting buttercream?

I don't like non-crusting.

With my crusting BC, I wait a few minutes for it to crust over. I then pipe on my lettering. If I make a mistake it lifts right off without much, if any, damage to the icing. I can lift off most decorations without have to re-ice the cake.

I can also lay chocolate transfers onto the cake and lift them off without sticky icing all over the backs of them, unless I have pressed it into the cake.

I like they look it has when it dries.

I just like it better. But it's a personal thing.

I prefer crusting buttercream also. I just think, for me, it's an easier surface to work on. I use the letter and pattern impressions alot and it's just easier to make the indentions on.

Hi,
cali and tika thanks for your help.