10 iPad Apps for Art/Design Lovers

Alice Yoo has put together a list of 10 apps for the iPad that are a must for art and design lovers. Her list includes Art Studio, Inspire Pro, Sketchbook Pro, Penultimate, iDraw, Brushes, Adobe Ideas, Art Authority, Moodboard, and iFontMaker. Which is the best one? Any thoughts, for I need to buy one.