The root element removal was a bug, I've fixed it for the next release. I've also updated your points for the find.
If you initialize the PanelBar with a dataSource object, it will remove all the items in it and recreate it using the new data (in effect from the service pack). However this will leave the events bound to the root element intact and you should call yourPanelbar.element.undelegate() before doing it (we will try to fix this for the next release).
Thank you for the div suggestion, actually this will probably happen with any other element as well. We will try to fix it for one of the next releases.
All the best,
the Telerik team
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