The Burst test is indeed the only Q-Check that report PO Errors (POE).
The Sum8, Sum1 and Basic tests all report PO Failures (POF) however.
"Failures" are "Errors" that could not be corrected by that ECC algorithm.
PIE are correctable Parity Inner Errors, PIF are Parity Inner Errors not correctable by the PI ECC (i.e. Failures), so the Parity Outer ECC is used instead. If both the PI and PO fail to correct an error you get a Parity Outer Failure - the worst kind, since the data could not be retrieved correctly (the drive will usually re-read the sector one or more times to try again however).
You DO NOT want any PO Failures on your discs!