i think rohloff can't be compared at the moment, they are much more expensive.
i have a old nexus 7 on my gazelle, the base lineof shimano. i think the bike has around 17-20.000 miles and only recently i started to notice some signs of wear. i don't know if it's the hub or just need new cables and calibration.
on an older bike i have the venerable SA 3 but isn't working.
nexus 7 has not huge spread in gear ratios, i probably use 5. gear changes are not superfast but i saw no difference at all when tested bikes with more modern and expensive hubs. i have no idea about maintenance, i'll study because isn't worth asking to the shop.