Ok ! Casio says the lightengine loose very few power over 20K hours (compared to lamp), i will see.
Yesterday, i tried 5 meters diagonal in eco 1 and the lightengine is sufficient in eco1 in the dark, it's very big 5 meters diagonal ^^.
But i prefer stay with 3 meters diagonal because of my projection screen.
My ultimate settings :
Brightness -20 contrast +5
mode colors cinema
Bal.colors normal with -10 red, 0 green, +50 blue
With my ps3, the results are very good with colors perfect now (with 130h use time).
After for a PC picture from the control pannel nvidia i use: brightness: 50%
contrast : 57%
gamma : +1.05
digital vibrance 65% but you can change it. It depends if you want less colors, you put less.