I am buffing up on ASP.NET Server Controls and a central dilemma seems to be whether to inherit from System.Web.UI.Control or System.Web.UI.WebControls.WebControl. It really seems to boil down to whether you will be presenting visual elements or not. If you are presenting visual elements in your control, you should probably inherit from WebControl. Why? Inheriting from System.Web.UI.Control basically gives you all that you need from the ASP.NET page framework but WebControl gives you the added control of applying styles to your controls as well as Attributes. A couple of these are AddAttributesToRender, ApplyStyle, CopyBaseAttributes, CreateControlStyle, and MergeStyle; none of which are available in Control. Using these methods with the base types and enums from Control (WebControl inherits Control and IAttributeAccessor) you have a very powerful mechanism for developing a Server Control
AND a readily available mechanism for making your controls visually pleasing.