The Discs should be burnt with the correct media ( verbatim ) is argubaly the best media available for OEM GPS duplication, there are conflicting reports on the speed the media should be burnt at. The Ideal speed tho really is the 2.4x speed.
If your using ***** media I would be very suprised if the standard HU even read the discs, as they are very fussy - hence why Verbatim is known for the greatest success and this media is expensive for a reason ( quality ) it's probably a better quality disc than Navteq use, or maybe even the same media!
I've got the latest version 3.52 ( west europe ) that I have done for a few people and it's been fine on every one of them.
I think this whole o it's going to ruin your dvd drive is a crock of *****. There's signs of anything struggling to read data, be it a pc or even a gps system if for example on the gps system the map was stuttering as you were driving along or the drive was loud then yer there would be issues. But again with Verbatim media this does not happen.
Verbatim works on all GPS system OEM.