This is a long, but very detailed starting point
A key part of this, is this snippet from the article.
[B]Easier explanation on how to read the test results.[/B]
Maybe this has got too technical, and you are wondering what to look for in KProbe reports?
Use this as a [B]guideline[/B] for good discs:
[li][B]PI (Parity Inner):[/B] No larger areas on the disc should exceed 280 PI-8 errors, do not worry too much about high single spikes that exceed 280.[/li][li][B]PIF (Parity Inner Failures):[/B] No larger areas on the disc should exceed 4 PIF-1 errors, do not worry too much about high single spikes that exceed 4.[/li][/ul]
And as always; lower is better