Unless you're going high-end, I would just recommend sticking with hubs that have cartridge bearings. You probably know your way around loose ball bearing hubs if you're into C&V, but a lot of modern ones are built so cheaply that they're not worth the trouble. I had a set of loose ball Formula hubs that needed the cones adjusted almost daily, and got pitted from regular use. The high-end stuff like Dura Ace and Campy Record are built well, but otherwise, go for cartridge bearings. Formula and Novatec are popular choices. H+Son rims are a top choice for many as well.