Performance Issue in RadListBox

[Kangming]

I seems experience very bad performance degrade when I use drag and drop RadListbox.  The version I use is RadControls for WPF Q1 2012 SP1.  Here is my xaml code for the lisbox:

<telerik:RadListBox ItemsSource="{Binding Offices}" DisplayMemberPath="Name" Height="Auto" Margin="10,0,0,10" Grid.Row="2" Grid.Column="1" Width="120">
    <telerik:RadListBox.DragVisualProvider>
        <teleric:ScreenshotDragVisualProvider />
    </telerik:RadListBox.DragVisualProvider>
    <telerik:RadListBox.DragDropBehavior>
        <teleric:ListBoxDragDropBehavior />
    </telerik:RadListBox.DragDropBehavior>
</telerik:RadListBox>

The Offices binding to ItemsSource above has about total 500 records and type is List<string>.  Any recommendations or solutions are welcome.
Thanks,

[Yana]

Hello Kangming,

We have tested the described case with both Q1 2012 SP1 and the latest Q1 2013 SP1 releases of RadControls, but weren't able to reproduce the performance issue. Please send us more details about your scenario and/or a  sample project demonstrating the problem.
Thanks in advance

All the best,
Yana
the Telerik team

[Kangming]

After I researched and tested last week, I am not able to reproduce the performance problem in a small scaled solution.  Therefore, we could close this discussion for now.
Thank you,