I broke two Deore and one SP PL-1. My cheap Nexus one seems to hold better but drags a lot. There’s a market for a hub that has serviceable bearings, especially with brake disks where it’s the only part of the wheel that’s supposed to experience wear. I’d love to be able to pop two new bearings in place and ride 10k more.
Unfortunately most dynohubs are essentially un-servicable. The ones that do claim some level of servicability (eg, SP) mention a very tricky re-alignment process when replacing the bearings that can only be done successfully at the factory. I've gone for an Alfine on my new commuter - it's been fine for the past year, will see how it goes.