Although I think texture is the predominant draw of asparagus, the flavor is singular too. The problem with asparagus is that, like corn, it loses its natural sugars extremely rapidly after harvest (which has to be done by hand, accounting for its relatively high price). Unlike corn, asparagus doesn’t have a lot of sugar to begin with, so picking the freshest stalks is key. Since diameter is unreliable, the only real visible clue is the tips. Tight tips, meaning the little buds on top are all still stuck together, mean fresher asparagus. Some people check the bases, but they don’t tell you much. As far as the differences between white, purple, and green asparagus, I’ve always preferred green. If there is any difference, it’s certainly not worth the premium you pay for white, which has been completely buried to prevent chlorophyll production, or purple, which is colored by reddish compounds called anthocyanins, which disappear when cooked to leave the chlorophyll of everyday green asparagus anyway.