Check this out...Sony is also a 4X! There's a firmware upgrade on their website.
Also, some 4X products on the market (TDK 4X indeo, for example) claim 4X speed but only for certain formats. See what I mean below:
Sony DRU500A specs:
Specifications top of page
• 2.4X max. DVD+R Write; 2.4X max. DVD+RW Write; 4X max. DVD-R Write; 2X max. DVD-RW Write; 8X max. DVD-ROM Read
• 4X, 12X, 16X, 24Xmax. CD-R Write; 4X, 10X max. CD-RW Write, 32X max. CD-ROM Read Random Access Time:
DVD: 200ms
CD: 160ms
• Buffer Memory: 8MB
• Buffer Underrun Protection Technology
• Supported disc format: DVD-ROM, DVD R, DVD RW, DVD-R, DVD-RW, CD-DA, CD-ROM (XA), Video CD, Photo CD (multi-session), CD Text, CD Extra and others.
Now here's the specs on the TDK 4X indio (which claims 4X speed)
Product Name Indi DVD
Model Number 420N
Minimum System Requirements Pentium II 500 MHz or equivalent
Windows 98SE/2000/ME/XP
128 MB of RAM
300 MB of available Hard Drive space
DVD Write Speed 4X
DVD Rewrite Speed 2.4X
DVD Read Speed 12X
CD Write Speed 16X
CD Read Speed 40X
CD Rewrite Speed 10X
CD Rip Speed 32X
Burst Read 16.6 MB/sec.
Data Buffer 2 MB
Playable Formats DVD-Video ROM, CD-DA, CD ROM+CD-DA, CD-Extra
Readable Formats DVD-ROM, DVD+RW (video and data), DVD+R (video and data), CD-DA, CD TEXT, CD-ROM, CD-ROM+CD-DA, CD-ROM XA, CD-I, Photo CD, CD EXTRA, CD-G,
Writeable Formats DVD+R (video and data), DVD+RW (video and data), CD-DA, CD-ROM (Mode 1), CD-ROM XA, Photo CD, VideoCD, CD-I, CD-Extra, CD Text
DVD Writing Modes Multisession (DVD+R), Sequential, Random Access (DVD+RW)
CD Writing Modes Track-at-Once, Disc-at-One, Session-at-Once, Multisession, Packet Writing