We have a lot of experience of portable DVD players in our house because my son is autistic and uses his one for a number of hours every day. He's had a Sony for a few years which has been good but I have to say that quality-wise this is at least as good.
The screen is excellent, very sharp and bright. It also responds quickly - which is a fault in many of the cheap brands. Even the Sony would take about 45 seconds to prepare to read a DIVX DVD but this does it in about 15 seconds.
I found the information about this player to be a bit vague and contradictory so I can confirm that is DOES come with a remote control - in fact it's virtually a necessity - see below.
We've not tested the battery in anger - but it certainly appears to be a good 4 hours minimum.
It does have some peculiarities though which may or may not be an issue or you:
1) The battery does not charge whilst he player is ON, it needs to be plugged-in but switched OFF.
2) The screen will not lean back from the upright position UNLESS it's rotated to the "back-to-front" position. In practice you therefore cant really use it without rotating the screen.
3) Normal fast-forward/reverse can't be done without using the remote control. Since my son likes to continually wind DVDs bacwards and forwards in short bursts - this means that he has to use the remote all of the time.
4) There is no Volume control on the remote - just a rotary on the side of the player.
5) The clever on-screen buttons are a nice feature - but mean that you basically have to press TWO buttons every time you want to do something. For example, if you want to pause, you need to press the button to SWITCH ON the buttons, then press the pause button. To start playing again, SWITCH ON again, then PLAY. In practice, I think the remote is easier to use.