Here I chose this calculator because it's been over 20 years I program on Casio. With a few buttons that have changed this place remains substantially the same, but what made me choose precisely this model is the backlight of the screen. Indeed we are not dealing with a gimmick, where in the dark becomes a simple screen difficult to read, just press Shift and then the screen light glows blue. I do not serve me of all functions, I mainly wanted to programming and a clear display even in the dark or black and is successful, and the screen is even better quality than older models. A purchase without hesitation!