We are aware of the appearance issue with RadButton in Design View in Visual Studio 2012. However, I cannot provide any time estimates for the fix as our developers are currently working on tasks with higher priority.
At the moment we are not aware of other issues related to RadControls suite in Visual Studio 2012. If you stumble, however, on such issue do not hesitate to report them to us, and will be glad to reward you with Telerik points for helping us improving the quality of the controls.
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