This "Essential Iliad" contains about one third of the Iliad. There is a somewhat different abridgment of this same translation in "The Essential Homer," which contains about (I reckon) 44% of the Iliad.
What does the extra 11% get you? A much better and more representative distillation of the Iliad, in my opinion. For example, the passages towards the end of the Iliad that show Achilles returned to the battle in all his fury over the death of Patroclus, spitting out famous bitter speeches about life and death, are in "Essential Homer" but not "Essential Iliad."
So get the "Essential Homer" instead.