Didn't buy it for AUD (don't think I knew it existed then :)) so I don't know how it covers international auditing - but I used NINJA notes for BEC and from my experience and what I've read on other posts the notes are very good and greatly beneficial. It's a good supplement.
It seems people are having different experiences regarding the testing of the international information. It looks like somthing that is being asked about more and more. Hopefully someone else here can give you better advice about this. I think that you should go over whatever information you can find on it, but don't lose focus on all the other material.
I used Becker and did pretty well on AUD, but I took the exam when (I think) they were beginning to test on international information.
Good luck!!
....Passed....
FAR - April '11
AUD - May '11
REG - July '11
BEC - November '11