  Ab-initio crystal structure prediction depends on accurate calculation of the
energies of competing structures. Many DFT codes are available that utilize
different approaches to solve the Kohn-Sham equation. We evaluate the
consistency of three software packages (WIEN2k, VASP and MuST) that utilize
three different methods (FL-APW, plane-wave pseudopotential and the KKR-Green's
Function methods) by comparing the relative total energies obtained for a set
of BCC and FCC binary metallic alloys. We focus on the impact of choices such
as muffin-tin $vs.$ full-potential, angular momentum cutoff and other important
KKR parameters. Different alloy systems prove more or less sensitive to these
choices, and we explain the differences through study of the angular variation
of their potentials. Our results can provide guidance in the application of KKR
as a total energy method for structure prediction.
