DrawUtility.UseGDIPlusTextRendering = false;
It seems ok, but when I run my app on Windows Vista, moving the mouse into ribbon area and then out, I see that the text in ribbon seem to be not stable. I think it's because when you play the fade effect on your ribbon, you don't care about GDI mode and use GDI+, so it happen.
But it's just happen in Window Vista :(
You should Submit an incident to Infragistics Developer Support
This is still not working correctly. I am on infragistics version 10.3, have the newer versions fixed this?
I'm also using the 2007 ribbon.