[charlie_ps2]

Your thread is addressed to the Experienced people. One of them (me) has said your burning speed is fine. (see my post CD-R Burning Speed in the factoids).

He (me) has also advised you that 1 in 4 or 5 of the v7s has a backup reading problem and I've suggested the laser azimuth adjustment.

Now I know you want to avoid troubling your installer, but he should have tested that everything works. Laser azimuth adjustment is an option available to him for getting the thing to work.