You won't be disappointed. I personally believe that BB10 is a great OS if not one of the best out there right now.

The Z10 I have never failed to slow down and the UI is one of the most fluid one I have ever seen. Is also one of the few OSes out there to support multitasking in its proper form.

Issue is BlackBerry itself. They are heavily, understandably, focused on enterprise customers.
Still I enjoy using BB10 A LOT after having used all Maemo devices and MeeGo ones and the Jolla now.

Only gripe I have, is the battery, but that's a removable one, so that's an easy to solve problem.