HLDS’s GBW-H10N is the world’s first and fastest Blu-Ray drive with production targeted for late this month. The GBW-H10N has a data transfer rate of 144Mbps, the fastest in the industry and can record and playback 25GB BD-R and BD-RE, in addition to DVD-RAM/R/RW, +R/RW disks. It can also playback BD-ROM, DVD-ROM and CD-ROM.
Image source: Reg Hardware
4x is achieved when recording on BD-R discs. Only 2x is achieved for BD-RE (rewriteable) discs. Dual-layer discs are not yet supported.