This exact problem is something I have only experienced with DVDs burned in a NEC ND-4551A and read and scanned in a BenQ DW1655.
I have had DVDs burned in a NEC 4551 which had slowdown problems in a LiteOn 1635S drive without showing problems in my other drives (not counting the BenQ and LiteOn 165P6S which I didn't have at the time), and which had good PIE/PIF scans. See this thread. The DVDs were readable but some had "damaged" sectors in ScanDisc on the LiteOn 1635S.
I have had one or two DVDs burned in a LiteOn 1635S that had unreadable sectors in both my LiteOn drives and my BenQ drives, but which read flawlessly in my other drives. I'm not sure how the PIE/PIF scans were because I didn't save the scans, but I think I might still have the disc(s) so I guess I could perform the scans again.
I have also had DVD burned in my Matshita UJ-840S laptop drive which had unreadable sectors and POF when read/scanned in my BenQ and the disc didn't show any problems in other drives.
So it's really a mixed bag, but in general the BenQ is the pickiest reader of all my drives and sometimes it doesn't even show any POF or even PIF for sectors in cannot read.
The LiteOn drives are generally excellent readers, but there are some discs where they are pickier than most other drives (except the BenQ).
The NEC 4551 is the worst burner, because it can produce discs that have transfer slowdowns in LiteOn drives and undreadable sectors in BenQ drives.
Are you confused yet?
The conclusions that can be made from all this are:
- A good PIE/PIF scan in a LiteOn or BenQ drive doesn't guarantee readability in the same drive.
- Some discs are readable in some drives and not in other drives, and this cannot always be detected by PIE/PIF scans in the drives that don't experience the reading problems.
- If you only use one drive for testing whether your DVDs can be read, you might be in for a nasty surprise when you try to read the disc in another drive of a different brand.