Indeed the maturity of our UI for ASP.NET AJAX suite (which exists for more than 6 years now) results in wider set of widgets compared to UI for ASP.NET MVC.
On the other hand, as a relatively young product (less than 2 years old), UI for ASP.NET MVC provides quite a lot of functionality and widgets. In addition, it is built on top of our Kendo UI framework, which makes it flexible for desktop and mobile platforms and devices. The suite will be actively developed in the future and you will see more and more features and widgets in it.
Hope this answers your question.
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