this is the one I have and it works awesome. Real simple hook up too, all you have to do is this. there are three wires to get power going. a red, black, and white. the red gets power from the postive of the batter, the black gets grounded, and the white is your ignition wire or acc wire. this wire will give the powersupply it's on/off power.
I have my monitor hooked up to the same power as my ignition and grounded to the frame, but I have added a secondary push button switch so that i can shut it off at will.
this works for me and i been using it for about a year now and have not had any problems with it.
Good luck and have fun