SPACI score report for 3mrg in ASTRAL 2.03:

PDB Entry: 3mrg
SPACI score: 0.74
AEROSPACI score: 0.74

Experiment type: XRAY
Resolution: 1.3
R-factor: 0.18
PCK1 PROCHECK Ramachandran: 1
PCK2 PROCHECK Chi-1 angle: 1
PCK3 PROCHECK H-bonds: 2
WCK1 WHAT_CHECK Packing: -0.118
WCK2 WHAT_CHECK Ramachandran: -0.996
WCK3 WHAT_CHECK Chi angles: 0.891
WCK4 WHAT_CHECK Backbone: 3.704

Note: Here are links to pages about PROCHECK and WHAT_CHECK.

Here is the full WHAT_CHECK report on this protein (linked from the WHAT_CHECK site).