I'm in the market for the same thing and I see that you posted almost a year ago. Let me know if you ever bought one and what your experience was like.
I need to keep my 3-year-old entertained for long trips and I have tons of DivX & avi files of her favorite shows. I've compared netbooks to portable dvd players and it appears that the portable dvd player outperforms a netbook for car viewing since it was specifically designed for this purpose.
But now I can't find a portable dvd player that doesn't have some deal-breaking defect - be it weird resolution specs, no divx/avi support, or low car compatibility.
Ideally I'd like the following:
--8+ inch screen @ standard ntsc resolution
--DivX & avi support
--SDHC slot (with divx & avi support)
--car lighter adapter
--car mounting kit (or one available)
--decent speaker volume
--decent resistance to skipping
If I had to give up one of these requirements, it would be the SDHC since I can just burn the avi files to a dvd.
Performance-wise, the toshiba sd-p2900 seems great - but it doesn't appear designed for car use. It only folds out like a notebook (not flat) and it requires a bulky battery. Reviews also say it skips too much for car use.
Does anyone have experience with a portable dvd that supports avi files and works well in the car?