Hi Josh Anderson,
Yes you can use the Q3 controls with your project. The license allows you to use any version of the RadControl for Asp.Net Ajax. Please take a look at the KB Article How to upgrade RadControls
Please note that we do not recommend upgrading. There might be some changes in the styles/functionality with the new versions. We recommend using only the controls that are provided with Sitefinity in order to avoid problems of that kind.
All the best,
the Telerik team
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