Some things don't cook well in them. Since you can't rely on people knowing how to care for them, you must patrol the kitchen when well-meaning guests volunteer to help out or to clean up. So, I always keep some cast iron in the stable for frying, but not a complete set of pots. Le Creuset . I don't have a lot of experience with it, but I've enjoyed using it from time to time at other people's houses.
Aluminum works great.
Handles metal utensils, and the occasional scouring. The latest I hear is that it does not cause Alzheimer's . Get the thickest you can because it will distribute the heat most evenly which means high temp cooking with less burning. One cheap place to buy them is a cookware outlet store in Kittery Maine. Or find a commercial cookware store.