Hi Craig Bolon,
First of all I want to apologize for the hard time you have had with RadComboBox. I know that from your point of view we have messed up but let me try to justify that change.
RadComboBox should now be with right size. They used to be 11px wider than needed (since the width was applied at the input element and the image width was not taken into account). I don't need to mention that lots of customers complained about that - for example you set the width to 100px but you end up with 111px because of the image.
RadComboBox indeed has a rendering issue which comes up from the limitation of the HTML standard and browsers.
We are currently trying to resolve that issue by inventing a completely new rendering. I really hope we will tackle this issue soon.
the Telerik team