Thank you for contacting us.
Complex components like RadControls couldn't be supported out of the box by any automation tool. That's why I'd answer "no", as far as we are aware there is no automation tool outside Telerik supporting RadControls as users would expect.
WebUI Test Studio on the other hand is a product we develop internally. Thus the RadControls support is very important for us and we make sure our support is up to date with the latest controls release.
I hope that answers your question. Do not hesitate to write back if you have further inquiries.
the Telerik team