The "badness" is dependent on how you use them. I typically use breaks in looping constructs ONLY when it will save me cycles that can't be saved through a refactoring of an algorithm. For instance, cycling through a collection looking for an item with a value in a specific property set to true. If all you need to know is that one of the items had this property set to true, once you achieve that result, a break is good to terminate the loop appropriately.

If using a break won't make the code specifically easier to read, shorter to run or save cycles in processing in a significant manner, then it's best not to use them. I tend to code to the "lowest common denominator" when possible to make sure that anyone who follows me can easily look at my code and figure out what's going on (I am not always successful at this). Breaks reduce that because they do introduce odd entry/exit points. Misused they can behave very much like an out of whack "goto" statement.