By far the easiest wheel removal is on the I-Motion 9. Shift to 1st gear, pull the quick release, and remove clickstick from the connector.
The prior Sram/Sachs hubs (P5 and S7) used a clickbox that was easy remove, but easy to break sitting outside the chainstay.
No experience with Nuvinci, but there are a few videos on youtube:
http://www.youtube.com/watch?v=NrJcptCzahc
http://www.youtube.com/watch?v=2Utm0...eature=related