As of Q1 2015 RadGridView exposes a new method – ExportToPdf which allows exporting to Pdf format without the need to integrate RadGridView with RadSpreadProcessing.
Another way would be to follow the approach illustrated in the "Print and Print Preview" online demo.
Alternatively, you can manually create the document to be exported. You can go through the articles about using the RadDocument and about the document viewer control - RadRichTextBox. You could as well review this article on how you could create the document elements.
You can also print data with RadSpreadProcessing, the model of which is completely independent from the UI. You can check the Export with RadSpreadProcessing example on how to do so.
In order to print or export with more advanced options you can check the Telerik Reporting product. You can find more information about it here.