Real simple: Are there things that you buy in stores that just have to be brand name, or can/do you go with the cheaper version? Also, can you tell a difference between the two (besides the price)?

For some things, I feel I need brand name and it's stuff like medicine, toiletries, and ketchup. Yep. I need my Heinz ketchup or I ain't happy. Other things, like most food items and drinks, I can get the cheaper brand because I really can't tell a difference in taste.