This gets asked quite often, and here's the standard answer.
No single drive can give you a good overall picture of DISC quality for each scanned disc with high probability. Many times scan result and disc burn quality match, sometimes they don't.
A scan tells you how well that DRIVE is able to read that DISC. So the error rate is always a combination of the reading drive and the disc being read.
If you want to average out a bit of the dependence on a single drive, you scan on three different drives of different model/make and you compare the results. The more they agree (less variance) and the lower the error rate, the higher the likelihood is that the DISC is good.
I scan with BenQ (1650), Plextor (760), LiteOn (DH20A4P) myself, but other combinations are possible as well. The more the better (and the more cumbersome).