Nothing to be worried about for a NEC scan (over-reports PIEs) even less so since i's a 16X scan.
The PIF peaks look like what's expected with some specks of dust (or other impurities on the surface) or small concentric scratches. Totally normal with most discs after some time, unless you handle them with utmost care, dust them carefully etc... (which I do, but we're not all freaks :bigsmile: ).
IMO nothing wrong with this scan, if the reading curve looks good (transfer rate test) this disc is still solid. Maybe you can take these PIF peaks as a hint that if you want to keep your discs for very long, you should check that you're not scratching them in some way without realising you're doing so.
And as cd pirate mentions, don't take your 4550 scans too seriously, these drive are notoriously looney for PIE/PIF scans. Among my favorite for transfer rate tests, though.