I know a number of ex-royal marines some SBS, pathfinder paras and more special ops types who have been working for the UAE army in the training roll, good guys one and all. The standard of the army here is not exceptional, UAE locals make up the officer ranks the rest are yemenis etc. They do not have the skills required for some of the more taxing scenarios. So the government wants some ex special ops guys to come here and cover a number of risk areas. Pretty sensible, they know there are weaknesses in the present forces, the threat is there, so they pay some highly trained guys to cover it. The guys get paid well so its good for them.
However Blackwater is another story, if it starts getting an air of respectability then one may forget its history which is not impressive. A second point is that mercs will not necessarily go as far in defending the state ie the UAE as a local guy would, they are in it for the money so when the !!!! hits the fan who is to say they will do what is expected of them!