I'm researching game development in Flash and Flex. I've downloaded the Flex Builder trial and have worked with older versions of Flash. I see that generally, Flex Builder is a developer's tool, and Flash is a designer's tool. It's not clear to me whether one is better suited to game development than the other, or if it's necessary to have both to effectively design games. To my mind, games are equal parts design/art and programming. Which tool is more commonly, or more intensively, used for game development?