SPACI score report for 1tw3 in ASTRAL 2.01:

PDB Entry: 1tw3
SPACI score: 0.36
AEROSPACI score: 0.36

Experiment type: XRAY
Resolution: 2.35
R-factor: 0.196
PCK1 PROCHECK Ramachandran: 1
PCK2 PROCHECK Chi-1 angle: 2
PCK3 PROCHECK H-bonds: 1
WCK1 WHAT_CHECK Packing: -1.395
WCK2 WHAT_CHECK Ramachandran: -1.58
WCK3 WHAT_CHECK Chi angles: -2.759
WCK4 WHAT_CHECK Backbone: -0.022

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).