Often people want to A/B or split test ads that vary on one dimension. This is easy to do in our system. You can build one completely, then, within the same group, duplicate the ad. Edit the duplicated ad as desired, and launch the ads at the same time. If you are interested in looking at performance differences across creative, Build a single campaign and put different creative assets in the same ad group. Our system will automatically let you compare them.
An upcoming version of our dashboard will allow you to compare campaigns side-by-side.