I also have an E616A2 and have found scans done on it are very similar to scans done on my Liteon 160P6S. If anything the ASUS tends to be a little less forgiving of PIEs. It also supports C2 detection on CDs, something a couple of my burners (BenQ and Pioneer) don’t do.
I’ve always heard burners are better scanners than DVD-ROM drives, but I’ve never heard a logical explanation of why they are. It seems the practical reason for scanning is to learn how some ultimate reader might “see” the disc. And probably more often than not, that reader will NOT be a burner.
I’m far more concerned about whether I’ll be able to play a movie in my picky DVD player for as many years as I’ll care to see it. It would be interesting to know specifically why a burner could tell me that better than a good DVD-ROM drive, especially since I’ve never found burners as a class to be more talented readers.