What do you think about flash extensions?

Hi, guys! I see sites like: www.flashdevelopment24.com which develops Dreamweaver extensions – flash components to sites such as, different flash galleries, maps, players and so on! And I have some questions… Can these or such flash extensions help you? Are they useful and is it clear how to use and work with them? Is anybody using them? And in general, what do you think about them?