Swampy,
I am an expat Capt. To answer your questions:
1) In 2 years i have only ever flown with another expat F/O 4 times;
2) Number of expat Capt's on 744 fleet is 90+ (no idea about other fleets). Number of local Capts on 744 is 130-150;
3) The books are usually clean. My previous company, one also much spoken of here in this PPRUNE forum, measured up very poorly in this area, where they used to carry lots of stuff in the DDL. This was indeed a breath of fresh air.
I agree that you come with your eyes wide open, take the money & the home leave and that's it. If you must come, make your decision based on what's on the table right this moment, not what seems to be implied will happen. If you can live with that, you'll probably do alright. Good luck