I took a good look at all your scans and I have to hand it to you, you certainly did your work. Thanks for all the effort.
My opinion still stands. While I admit my standards are very high, the only media I would use, based on your scans, is the MCC 003, the MBI media, and the Ritek R03. Of these, both MBI and Ritek are widely variable in quality so that leaves me with MCC 003 as an acceptible media, and even then the number of PIF errors are 5 times as high, but the PIF are much lower.
The rest either have total PIF/PIE or levels of PIF that are higher than acceptible (for me). I would also be disturbed by the number of media that just go weird.
While I have no doubt that NEC will get their act together I will still keep my 3520 for a while. I well remember how long it took for the 3520 to get over its initial problems. We were all griping about it not that long ago and now it is close to the 3500 in most ways, and better in some.
It is hard to compare scans from an NEC to those I get from Liteon. Maybe your media scanned on my Liteon would look better. I know when I scan with my 3520 it is often way worse than Liteon.