The Sony DVD Walkman may support a lot of mainstream disc formats—DVD RW, CD RW and VCD—but its lack of DivX and XviD support may leave more advanced users looking elsewhere.
Otherwise, the 5.1 audio sounds great, and the 7" screen is enough for watching on the go. The only problem comes from the non-embedded speakers in the actual player itself. If you don't take the rather hefty dock with you, your only choice is to use headphones or some other type of portable speakers. This makes it not so convenient when you want to share audio with someone else when watching.
All in all, it's pretty much a standard DVD player with the Sony Walkman name attached. Stylish design may not win out over its relatively steep price compared to generic units.
Review: Sony DVD Walkman [Tech Digest]