Since many new field guides are published each year, it's not easy for one to rise above the pack. But this book - Birds of the Middle East, Second Edition - by Richard Porter and Simon Aspinall (Princeton University Press) is the obvious choice for "first place" for me.
The reasons? The artwork is spectacularly good. Images of many plumages are included. The authors have expanded their coverage of species by 1oo over those found in the first edition - there are now more than 800. There are more species accounts and more than 820 maps. Maps are on the facing page, which is still not true for all field guides. The book is still really "field guide-size" - making it easier to actually use in the field.
For those heading to the Middle East, this book should make birding easier for you. And I pick it up every few days just to look at some of the plates, (owls, for example...and large falcons...and the many Middle Eastern wheatear species!)