No CDFreaks Review as yet (see the update below)

Specifications from Pioneer AU

# Maximum Write Speed:
# - DVD-R 1X, 2X, 4X, 6X, 8X*, 12X*, 16X*
# - DVD-R Dual Layer 2X, 4X, 6X
# - DVD-RW 1X, 2X, 4X, 6X
# - DVD+R 2.4X, 4X, 6X, 8X*, 12X*, 16X*
# - DVD+R Double Layer 2.4X, 4X, 6X
# - DVD+RW 2.4X, 4X, 6X, 8X#
# - CD-R 4X, 10X, 16X, 32X*, 40X*
# - CD-RW 4X, 10X, 16X, 20X#, 24X#
# Writing Formats: # ZCLV, * CAV
# ATAPI Interface
# Supports "Buffer Under Run" protection 2Mbytes
# Vertical and Horizontal Mounting

PERFORMANCE REQUIREMENT:
To achieve the specified writing and reading performance it is important that the DVR-109 is connected to the IDE port via an 80 way ribbon cable and that the IDE port is at least UDMA 66 or above.

Read Support
DVD
DVD-ROM (single layer and DL), DVD-R, DVD-RW, DVD+R, DVD-R DL (Dual Layer), DVD+R DL*3 (Double Layer), DVD+RW, DVD-RAM (Non-cartridge DVD-RAM Version 2.0/2.1 only)

CD
CD-ROM(Mode 1), CD-ROM XA Mode 2 (form1, form 2), CD-DA, CD-Extra (CD Plus), Video CD, PhotoCD (single/multi-session), CD-Text, CD-R, CD-RW (High-speed CD-RW, Ultra Speed CD-RW)

Update: Here's the CDF-review of the Pioneer 109