I guess if you're comfortable working in a country whose infrastructure depends on slavery, then it's probably an OK country to work in. So long as you don't fall afoul of the corrupt officials, the medieval "justice" system, and don't get into a disagreement with a national, in which case I hope you have a solid exit plan. A very solid exit plan.
Yes, I've worked in the Middle East (various places). It was very profitable, and I probably could have stayed. But I eventually I found it morally indefensible for someone who didn't want to be a complete hypocrite, and I never could agree that slavery was a good thing, no matter what the Qu'ran (or the Bible for that matter) might have to say about it.
So if money is all you care about, by all means work in the Middle East. So long as you're feeling lucky of course. Get into an argument with the local authorities (or worse, with a well connected national. Watch out for those low-numbered plates in the UAE for instance) and you're going to discover just how inhumane the system becomes. And most often definitely not in your favour.