Well about screen brightness in my view is ok but I am having trouble when i drive in day time as i cannot see whats on the screen even with the high brightness! there is an option for night time view and day time view! for cd version u can get it for 32k i think with 6 months warranty! and quick back camera response too and OS is simple, tried bluetooth handsfree as well, fulfills your requirements while driving! no lag, but havnt tried videos in it! how can you watch a video while driving! 