I'm the kind of coffee drinker who would rather go without and brave a thumping headache, then drink a bad cup. What's a bad cup? Well, that would differ from person to person but it's pretty simple for me; tar-thick sludge is a big no-no, especially if it comes with little actual coffee flavour. Sour coffee is another turnoff - a little acidity, even more than a bit is fine, as long as it's part of the inherent character of the coffee, not a result of brewed coffee standing around on a heate...