OK so I think I figured out what is going on with the vertical lines in the flashing bar brightness pattern. I can absolutely see them on on my RS40 as well. On bar 24 there is a lighter line and on bar 22 there is a darker line and another on bar 18. Oddly, if you look at the bars below where the white numbers are (bottom of the screen) the lines do not exist there. Also, depending on how you have you gamma controls set , especially picture tone, there is some odd banding that will show up on certain bars. It will become more or less evident or go away completely with changes to the 3 gamma controls and how you have your brightness set.
Since I can see the vertical lines in exactly the same place on the RS40, it has to be the disc. The banding is some flukey thing with either the gamma controls, the controls interaction with that pattern, or something like that. But since I can make it go away I am thinking anyone actually looking hard enough would find this to be the same.
Very odd, but at least I think my PJ is fine, or at least the same as any 4910.