Thanks a lot for the nice words! RadControls "Prometheus" is built upon ASP.NET Ajax and it is impossible to exclude the ScriptManager control from the page. I have made some tests and it seems that the ScriptManager alone brings just about 50KB of overhead for the page. These scripts are essential to the Prometheus web framework and are required even if no AJAX is needed. Unfortunately this is the price to pay for leveraging the ASP.NET AJAX platform in our new suite of controls.
We apologize if this causes a big inconvenience.
the Telerik team