Best of its class. The product gets you much closer to being able to reproduce fully featured Office style interfaces than anything else we have seen. I rated it as 4 * rather than 5 because not every element of the suite is finished to the same level of content and robustness. The menu, edit and toolbar components are totally excellent. The side bar and VS.Net style popup windows are in contrast unusable - hopefuly this will be addressed in the near future - but these are not essential elements and do not detract from the overall usefullness of the product. Support, code examples and documentation are all excellent. This product is a real productivity aid to a thick client .net application and fills in most of the (bizarre) gaps in the default MS libraries.