Jambo. No question.
Kidani is a lovely resort. We stayed there a couple of years ago. Horribly inconvenient. The simple lack of counter service is enough of a minus to overshadow all of the plusses.
The pool is beautiful....but you can use it if you are at Jambo.
The kids club is a nice distraction, but there is always something going on for kids at Jambo...much more so than other resorts. (bead activities, cookie decorating, drum lessons, night viewing goggles, etc)
The walk to most rooms at Kidani is also verrrrry long, though the views are stunning.
Stay at Jambo, play at Kidani if you have time. JMO.