My mother owns a Moto X, bought on my recommendation. It is much closer in width to my Nexus 5 than it is to the iPhone and barely more comfortable for me to use one-handed than my Nexus 5. The difference in width is apparent in the photograph you linked.
I commend Motorola for an excellent job eliminating non-screen area on the front of the Moto X. It's a very space-efficient device in that regard, but my complaint is about reaching all areas of a touchscreen with my thumb while holding it in one hand, and nothing fixes that like a smaller touchscreen.