Good question. There is indeed a lot of overlapping functionality, which both Kendo and Angular provide but in different ways. If you already use Kendo but not Angular, my suggestion is to continue to do so, and you don't need the Angular-Kendo bindings.
FYI, we currently support Angular 1.x, but Angular 2.0 is in the works
and it looks like it won't be a simple drop-in replacement (different API, written in EcmaScript 6). That's something we don't do at Kendo -- our motto is "no breaking changes!" (except perhaps with very good justification).
The bindings were created for Angular users -- that is, the goal was to provide a UI toolkit for people who already use Angular but perhaps not using Kendo. By creating Angular directives for Kendo widgets we provide a familiar API and behavior for Angular users.
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