Please see this image, sorry I do not have a lot of PIE/PIF scans-just saved some screens in the xls.
But I combined image from 3 scans:
there was multisession DVD+R recorded by 11 drives and after scans by BENQ 1620
and also jitter scans by two Plextor B950SA with same FW.
I think it depends on the lens alignment of both writing and reading drives.
For example, the Jitter level measured by two identical Plextors is very different, the PIE/PIF level was also different.
I do such multisessions to choose which drive is better to record a particular batch of disks. And periodically it's not easy to choose
due to mixed results from different scans on different drives.
same disc: compare the results from Plextor #1 scans especially the last session around 3 Gb and some others
