I never foil my ribs. I have tried it and I don't like the texture. Prior to having an Egg I cooked ribs in either a WSM or my Ace of Hearts Rodeo (formerly The Good One model 42). Both have a vertical airflow similar to an Egg so I don't think I will start foiling with the Egg. My theory (totally un-tested) is that cookers with a horizontal airflow like a traditional offset can dry out the meat due to the air passing over the surface of the meat while cookers with a vertical airflow like an Egg don't dry out the meat as much since the airflow is around the meat not across the meat.