We have four European City bikes with IGH's. Three Retrovelos and a Workcycles. All four bikes, are heavy-duty, steel-framed, heavy urban bikes.

The Retrovelo Paul and Paula have Nexus 8-speed IGH's and roller brakes. We've found the Nexus hubs to be pretty foolproof. We did have to swap out the rear cog on the Paula to cope with the long steep hills in Seattle, but that was easy. The roller brakes are OK for flat country, but in hilly country like Seattle, there are a little anemic on long descents. Probably best for riders weighing well under 200 lbs. The Paul is ridden in Tucson, where it is very flat and the Nexus hub and roller brakes work great.

We also have a Retrovelo Alfons with an Alfine 11-speed hub, which is wonderful. That bike is ridden in Seattle too, and both the chainring and rear cog were swapped to lower the overall gearing. With the lower gearing it is nice to have the 11 speeds, so there is still a good top end. Like mentioned by someone else, the Alfine hubs use an oil bath instead of grease and I just recently changed my oil for the first time. It was pretty easy to do. You change the oil through a port in the hub at about 700 miles and then every couple of years thereafter. The hub does not require disassembly to change the oil. The Alfons came with disc brakes, which have been upgraded in the front from 160 mm to 203mm rotors - again, to cope with a large rider on Seattle's big hills. This would not be necessary in flat country.

Finally, we have a WorkCycles Secret Service with a NuVinci 360 CVT rear hub. The Nuvinci appears to be a absolutely bulletproof. We like that it has continuously variable gearing, rather than discrete speeds. That bike is ridden in Tucson, where it is flat and the weight of the bike and hub is not a factor.

Bottomline, all three IGH's, the Nexus 8-speed, Alfine 11-speed and NuVinci 360 have worked great for us.