SPACI score report for 2a4w in ASTRAL 2.07:

PDB Entry: 2a4w
SPACI score: 0.58
AEROSPACI score: 0.58

Experiment type: XRAY
Resolution: 1.5
R-factor: 0.205
PCK1 PROCHECK Ramachandran: 1
PCK2 PROCHECK Chi-1 angle: 2
PCK3 PROCHECK H-bonds: 2
WCK1 WHAT_CHECK Packing: -1.133
WCK2 WHAT_CHECK Ramachandran: -0.172
WCK3 WHAT_CHECK Chi angles: -2.219
WCK4 WHAT_CHECK Backbone: 1.156

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).