Thank you for your interest in RadControls for WinForms.
If I understand your case correctly, you are concerning the fact that the text of the title of a toolwindow and the same text in the vertical mode look different. We use the GDI+ functionality to paint our texts and the way the text is rendered cannot be changed. I also checked how the mentioned competitor works in this case and it seems that they behave the same way.
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the Telerik team
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