Just thought I would add my own comments to the thread.
Although I have my Trek Super Commuter 9+ up for sale, will fund my new e recumbent trike purchase.
So, I have had the NuVinci 380 hub on the Trek, and ridden about 1800 miles with it. I have also owned a Rohloff hub in the past.
The NuVinci does exactly what it says, step less gear changes and very smooth.
The ability to make very small changes to the gear ratio is also very useful.
In fact, the straight chain line has been very kind to chain life.
I have two chains, which I rotate every 500 miles, hardly any noticeable stretch on either chain.
In contrast, the rohloff was similar and had a wider range, but with the ebike power I would class it as a little overkill. Certainly haven’t wished for more gear range and I live in hilly South Wales.
Rohloff is fine, probably less drag, lighter in weight, but more suited in my opinion to a non ebike.