SPACI score report for 1t6z in ASTRAL 1.69:

PDB Entry: 1t6z
SPACI score: 0.3
AEROSPACI score: 0.3

Experiment type: XRAY
Resolution: 2.4
R-factor: 0.225
PCK1 PROCHECK Ramachandran: 1
PCK2 PROCHECK Chi-1 angle: 2
PCK3 PROCHECK H-bonds: 2
WCK1 WHAT_CHECK Packing: 0.425
WCK2 WHAT_CHECK Ramachandran: -2.176
WCK3 WHAT_CHECK Chi angles: -1.824
WCK4 WHAT_CHECK Backbone: -6.597

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).