Thesis and Genesis are both great theme frameworks for WordPress. They both have their advantages. Starting a website based on these frameworks is a very smart idea. The Derby theme is a cool child theme that is compatible with both frameworks. It has a responsive design and has everything you need to start promoting your business like a pro.
Derby has a quite an elegant design. In order to take advantage of it, you are going to need the latest version of Thesis or Genesis. It has a cool slider with optional captions. The built-in Design Tool makes customizing various aspects of this theme easier. You get multiple colors and page layouts. The landing page template is especially useful for product promotion.
Derby for Thesis & Genesis is a pretty decent looking theme for anyone looking to use those frameworks to build a business portal. It is responsive and easy to customize. If you know your way around Thesis/Genesis, you are going to have an even easier time getting this theme to work.