actually sour candy is bad for your teeth, especially sweettarts. they have the exact amount of acid/sugar to rot your teeth on contact.
Sour Skittles are dreadful.
The first 2 or 3 are great, after that, I my mouth is just in pain.
And I think lemons are delicious, if you feel like saying "you're a pusillanimous individual" or some crap like that.