In this case you get the best of both worlds - if you mock the third-party API you can do TDD on all of your code, but you still get all the thrill and excitement of debugging when the API doesn't behave entirely as advertised!
They really are all crap. Run leaks - playhaven, tapjoy, flurry, etc are all guaranteed to be there. They dont even run static analyzer, which find some of these.