SPACI score report for 4ar6 in ASTRAL 2.07:

PDB Entry: 4ar6
SPACI score: 1.13
AEROSPACI score: 1.13

Experiment type: XRAY
Resolution: 0.92
R-factor: 0.1288
PCK1 PROCHECK Ramachandran: 1
PCK2 PROCHECK Chi-1 angle: 1
PCK3 PROCHECK H-bonds: 2
WCK1 WHAT_CHECK Packing: 1.505
WCK2 WHAT_CHECK Ramachandran: 2.219
WCK3 WHAT_CHECK Chi angles: 1.499
WCK4 WHAT_CHECK Backbone: 4.676

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).