SPACI score report for 2aa3 in ASTRAL 2.05:

PDB Entry: 2aa3
SPACI score: 0.43
AEROSPACI score: 0.43

Experiment type: XRAY
Resolution: 2.05
R-factor: 0.192
PCK1 PROCHECK Ramachandran: 1
PCK2 PROCHECK Chi-1 angle: 1
PCK3 PROCHECK H-bonds: 2
WCK1 WHAT_CHECK Packing: 0.479
WCK2 WHAT_CHECK Ramachandran: -1.621
WCK3 WHAT_CHECK Chi angles: -1.631
WCK4 WHAT_CHECK Backbone: -1.302

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).