Since I read those over the course of a couple of months while reading the main series, I'm not gonna to a detailed review. I'll just leave the scores I put down after finishing each of those short stories:

Drive 3.5/5 

The Churn 3/5

The Butcher of Anderson Station 3.5/5

Gods of Risk 4/5

A Vital Abyss 2/5

Strange Dogs 4.5/5

Auberon 4/5 

The Sins of Our Fathers 3/5

 ... and that averages out to about 3.5 stars. :)