I know, I know…I have famously frightened away hundreds of people from eating mussels. But you’ll be handling and cooking these mussels yourselves, and presumably you’ll be more conscientious than some college student with a part-time cook’s job at a sports bar.
Mussels are beautiful. Mussels are delicious. Mussels are easy as hell to cook. Just make sure you buy nice, fresh, still-living mussels (cultivated or wild, as you wish). Wash them carefully in cold water, store them—if you are storing them—in the refrigerator, in a raised slotted pan or colander so they can be separated from whatever may drain out of them, and before beginning to cook, make sure that they are all closed. If there are open ones, tap them lightly and see if they then begin to close. If a few stay open and don’t respond? Throw those out.