From all my drives (BenQ, LG, NEC, LiteOn, Pioneer etc.), I get the best and most reliable results with my Pioneer DVR-215 when it comes to DL media. I use Verbatim DL media exclusively, and it does an excellent job with both 2.4x and 8x Verbatim DL media (MKM001 and MKM003).
The DVR-215 will rip DL media up to 12x. It’s not the best reader out there, but it still does a good job when it comes to reading. I use mine exclusively for burning though.
The drawbacks of the drive, e.g. no bitsetting, can be fixed with the great tool MediaCodeSpeedEdit, but you will void your warranty using it.