Yeah I just got the DRU700A. But I can't help much since I've only burnt one single layer DVD so far. I don't even have any dual layer media to try. I though the drive might come with one since they are so new but it didn't.

Don't know about it being a LiteOn, but the guys over at anandtech say it's the same as a Gigabyte single layer internally and that the Gigabyte burnt a dual layer disk with some special beta firmware. Seehere

Dual layer is also quite slow to burn in case you didn't know. 8x for single layer vs 2.4x for dual layer (and I think 2.4x on both layers).

Seems to work so far although I know that doesn't help much.