According to April's product roadmap, these drives were supposed to support the DVD-RW DL format. However, looking at the specs on Lite-On's website, that doesn't seem to be the case. More information on all four drives can be found here.
Writing Speeds: DVD±R: 20x Max
DVD±R DL: 8x Max
DVD+RW: 8x Max
DVD-RW: 6x Max
DVD-RAM 12x Max
CD-R: 48x Max
CD-RW: 32x MaxRead Speeds: DVD-ROM: 16x Max
Access Times:
CD-ROM: 48x MaxDVD-ROM: 160ms
CD-ROM: 160ms