I love to airbrush my fondant cakes, but I have a client who wants it on buttercream. I'm not sure what type is better (crusting, non-crusting, etc...). I normally use SMBC on my cakes, but I know this won't work.

I prefer airbrush a crusting buttercream. A non-crusting will work also, just make sure its a good consistency and won't melt or it will not be pretty.

Thanks!!!

Yep, no airbrushing on SMBC.  It will work on cream cheese icing or ABC.  Or, of course, fondant.

Wow! I never thought of cream cheese icing. Thanks for your help:)