Sorry for taking so long to respond to this issue, but I was on the road, and then when I returned I had to test on a number of systems to try and duplicate.
Unfortuneately, I can not duplicate this issue. I've tested this using files from 3.5gig in size up to 9gig and could not get it to fail during a read verify. I've tested on Windows 98SE, Me, 2000, and XP with all the latest system upgrades, and after repeated tests I could not get this to fail.
I have the same Sony model recorder, and DVD-RW media. I've even tested with other recorders and media and could not duplicate.