The RadXmlHttpPanel's panel is able to provide better performance because, unlike AJAX,
ASP.NET Callbacks do not go through the entire page lifecycle, but only through
a small part of it. The data, returned from the server is also significantly smaller than the typical
AJAX response -
it is the data needed to update the content of the RadXmlHttpPanel only. No hidden variables,
such as the ViewState content, are returned.