I think that the answers to questions #5 and #6 in the public MVC FAQ
summarize the information you are looking for.
Kendo UI is appropriate for client development when one of your main goals support desktop and mobile platforms. Telerik Extensions for ASP.NET MVC, on the other hand, supply all the needed features you would expect from native MVC extensions and built-in robust support for WebForms and Razor view engines.
For your particular case (judging from the description you provided), you may consider using either solely Kendo UI Web or a combination of Kendo UI and our MVC extensions, if suitable. Note that in long term we plan to converge the two products to make use of the best that both worlds put on the table.
I hope this info helps.
the Telerik team
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