I apologize for the delay in responding to you. Here are answers to your questions.
1) Art of Test and the Telerik Testing Framework are the same thing. Art Of Test is simply an earlier name.
2) Your approach to testing AJAX items on a page should be the same regardless of the test tool you're using: you first need to ensure the AJAX call has completed and populated the elements you're looking to validate or interact with. Generally you can do this by first invoking a wait condition on the element, then moving to the next step (validation, selection, etc.) You may find this video helpful -- it covers those exact steps. The video's using Test Studio, but the same concepts apply to any AJAX test regardless of the testing tool/framework. http://tv.telerik.com/watch/automated-testing-tools/ajax-working-with-dynamically-loaded-elements
3) You don't need to use Telerik's test framework with our RadControls. Our Telerik Test Framework provides additional capabilities when working with Telerik controls, but you can follow the same basic guidelines for any AJAX control and successfully write tests with any testing framework. Unfortunately, we don't have any documentation specific to Visual Studio's testing features.
the Telerik team
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