The readability of the DVD in different DVD players and DVD drives can vary depending on the media, and depending on the burner and burn speed used. Some combinations of media/drive/burnspeed may read/play perfectly while others freeze or skip in some players or have reading problems in some drives.
For me, I get best playability with TY 16x DVD+R and TY 8x DVD+R media, while TY 16x DVD-R media needs to be burned in the right drive in order to play without skipping/freezing in my pickiest DVD player. I haven’t tested TY 8x DVD-R media enough to have an opinion on playability, but I know that others have reported that it’s not as good for them as TY 8x DVD+R.
In my experience you cannot predict playability of a DVD in picky DVD players by looking at PIE/PIF scans, unless the scans are absolutely horrible, so comparing PIE/PIF for this purpose is only useful when you’re testing the same media burned at different speeds or in different drives, but it’s not useful for comparing different media.