We live in San Antonio and have memberships at both Sam's and Costco. Both are the same distance from our home and we shop at both. Quite frankly, I see absolutely no difference in grocery quality between the two. Both are very good, and the quality of meat at either, particularly the beef, is way above HEB's. My wife prefers to shop at Costco, but ONLY because the aisles are a bit wider, and the lighting in brighter due to the white painted ceilings. I will admit that it is a more consumer friendly environment than our Sam's store. We shop at both because they do offer some different options from time to time. You just have to watch both as their inventory rotations changes frequently.