We all live in different parts of the country, so we all have different grocery stores, even if some are connected nationwide.
Out my way, I would say Vons and Stater Bros. are the best, followed by Ralph's, Albertsons, Winco, Food 4 Less, Aldis, etc..
Thing is, each store has it's plusses and minuses. For produce, Von's resigns supreme! Stater Bros. meat department is the best. Ralph's has the most variety of food and goods and Winco is great for those on a budget, plus they have the best selection of spices along with being one of the cheapest grocery stores around the area.
So, for me, I go to all these stores for specific things. The site I frequent the most is Von's.