None much, to be honest. I buy at Gadis and Eroski as the lesser evils (also Lidl for some processed stuff, but not for fresh products). But if I want good fruit, I go to a small fruit store, which is more expensive, but I find to have much better and more consistent quality fruit.
(Not that you can trust any small fruit store either... but some are good).
(Not that you can trust any small fruit store either... but some are good).