I would say it depends on the amount of life you have, what character you're using, and who's dictating the match-up. If it's a close round, and you're not 100% positive that you can take the round after they break, but you can end the round in unbreakable damage, then I would say take the round. However, there are too many variables to say that it is always a good idea to "force" a breaker.
Generally, yes.
Always, no.