One of the great things about ASP.NET WebForms was that it was very easy to create reuseable custom controls and components, but with appearance of ASP.NET MVC and lots of developers moving towards it, which is a good thing.
Sometimes when registering classes on Windsor container, that extend an existing base class with an interface, using auto registration and FirstInterface method is useless, because first interface finds the interface implemented by base class.
One of the good grid controls in WPF world belongs to Infragistics. With all the bells and whistles, there are still some limitation, some are WPF engine limitation and some are not. One thing that is very limiting is validation of data prior them being added to datasource.