SPACI score report for 4aah in ASTRAL 2.06:

PDB Entry: 4aah
SPACI score: 0.38
AEROSPACI score: 0.38

Experiment type: XRAY
Resolution: 2.4
R-factor: 0.152
PCK1 PROCHECK Ramachandran: 1
PCK2 PROCHECK Chi-1 angle: 2
PCK3 PROCHECK H-bonds: 2
WCK1 WHAT_CHECK Packing: -2.127
WCK2 WHAT_CHECK Ramachandran: -2.423
WCK3 WHAT_CHECK Chi angles: -3.177
WCK4 WHAT_CHECK Backbone: 1.319

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).