WebDynpro or JSPDynPage with HTMLB

We'd like to develop JavaApplications (PortalService, EJB,..) that will be called through a Portal-iView.

Some people from SAP say that it is better to use Java-iViews for frontend and others say that WebDynpro is strategic.

When looking at it, Java-iViews run inside the PortalPage where WebDynpro is always integrated by a generic WebDynpro-Java-iView using URL-isolation (IFRAME). This means that the browser always calls the WebDynpro-Content as if it comes from a dedicated server.

But WebDynpro has an easier and more standardized UI-design than HTMLB.

What are other pro/con's or recommendations?