Currently the AJAX suit of our controls doesn't provide an equivalent to the jQuerty Tagit control. Nevertheless there are a couple of controls which you could find interesting. The first one is our RadTagCloud control which provides a collection of predefined user tags. Here
you could find a demo of this control. The second control as you have already found is the RadComboBox. It's in fact useful for multiple selection which is one of your requirements. The code library which you have pointed is showing functionality which is already build-in. Please refer to the following demo
regarding the check box support of the RadComboBox.
the Telerik team
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