My local retailers carry the 321 and everyone online carries the 311. What's the difference? Is the 321 just the retail version?

If so, is it worth getting the software or just getting the 311 and different software? I've seen two different software packages:

Software: Power DVD, Power VCR, Power Director, Sonic DVD IT SE 2.5.2, VOB Instant CD/DVD

or

WinDVD 2000, MotionDV STUDIO, DVDit! LE, MediaSafe, FileSafe, DVD Agent, DVD-MovieAlbum SE

I'm already getting Nero by the way.