Deraillers are a bit more efficient (almost no loss) and overall simpler to work on. They also (generally) offer a wider range of geear ratios. Internal hubs w

Deraillers are a bit more efficient (almost no loss) and overall simpler to work on. They also (generally) offer a wider range of geear ratios. Internal hubs work great, but have a bit more loss, tend to weigh more, and when they start going sideways tend to go really wrong. But for the commuter-y / daily use like what you mention they tend to last and be more weather resistant. Because of all of this they haven't found a place in much hobby/fitness mountain or road biking, but are really great for less hilly utilitarian needs.