I tested it creaming butter. It didn’t eliminate the need for scraping because a fairly thick circle of butter formed right above where the blade met the side of the bowl; even after scraping it down, it reformed immediately. On the plus side, it creamed the butter a lot more effectively than the metal blade that came with the unit, which couldn’t reach a thin layer of butter lying against the surface of the metal bowl.
The SideSwipe I had on my KA was a lot better about not forming the line above the blades; the SideSwipe’s blades are angled slightly downwards, tending to throw the butter/batter back down into the bowl, rather than allowing it to creep up past the blade. Since the Beater Blade is one continuous strip of silicone, rather than individual blades, it can’t be angled in a similar fashion. The SideSwipe was also easier to install, since it was designed for the particular mixer, whereas the Beater Blade fits both Viking and Cuisinart mixers and requires adjustment to fit properly.
Given the choice, I’d take the SideSwipe, but, unfortunately, they don’t make it for the Cusinart. They say maybe in the summer of 2012.