SPACI score report for 3r4u in ASTRAL 2.06:

PDB Entry: 3r4u
SPACI score: 0.43
AEROSPACI score: 0.43

Experiment type: XRAY
Resolution: 2.2
R-factor: 0.173
PCK1 PROCHECK Ramachandran: 1
PCK2 PROCHECK Chi-1 angle: 1
PCK3 PROCHECK H-bonds: 2
WCK1 WHAT_CHECK Packing: -0.836
WCK2 WHAT_CHECK Ramachandran: -1.581
WCK3 WHAT_CHECK Chi angles: -0.375
WCK4 WHAT_CHECK Backbone: 1.923

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).