After a few days of riding with the derailleur gearing (with the motor not wired in yet) one thing that has struck me is how much easier the bike seems to ride. As an example this morning I was able to cycle the two kids and their heavy bags up the hill to school in my 3rd and 4th lowest gears (15.5 and 18.1 gear inches). Previously with the Nexus hub I used to have to do this in the lowest gears (11.7 and 13.7 gear inches). And I might add that I am not as fit as I was when I was pedalling around with the Nexus! I also did a 3km ride today to the bike shop and managed to do it a couple of minutes quicker then I had before by being able to pedal in higher gears then what I used to.
Maybe it is my imagination but I had read that internal gear hubs are not as 'efficient' as derailleurs and can introduce some 'drag' and I would have to agree based on my short experience!