Tastes awful to me. Our fridge has a filter and that's the only way I'd drink it. True it does have tons of fluoride in it but unlike many people I'm not convinced that's a good thing - even if you take the views of the idiot fringe away there's a large body of evidence that suggests it's not the positive additive it's long been thought to be (much of the modern research has been to answer why has there been such an increase in thyroid cancer in the last few decades). Its inclusion in water is based on very little research that took place in 1945 - a great many studies since have shown it has more disadvantages than advantages. A quick academic search is useful if anyone wants a good scare!
Incidentally, Monty, that patchy staining you mention is called dental fluorosis - the most commonly reported problem with fluoride in water (it means the tooth enamel is failing and can lead to pitted and brittle teeth). Might be worth thinking about spring water.