For urban commuting I love the IGH (currently 8 speed Alfine, would like to try the 11). Today I almost got doored, managed to check it down quickly (discs) and avoid the collision, clicked down three gears and I was back in business. I love the ability to react to rapidly changing road conditions/hazards and shifting later as needed.
As other posters have pointed out, shifter adjustment is more finicky and changing tires is more of a pain, but in the grand maintenance scheme these are trivial considerations to me, given how maintenance-free this hub has been for me.
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Work is the curse of the drinking classes - Oscar Wilde