Basically LED does absolutely nothing for picture quality. Its not going to offer more accurate or saturated colors.
You will get thin and lower power consumption. Neither affects gaming performance or photography.
In fact if you are going for photography I recommend the Dell U2311 with that budget.
It doesn't have LED backlights but the color displaying mechanism is fundamentally different. It uses an e-IPS LCD panel rather than a cheap TN panel which most monitors offer these days. Its not the best but it is a lot better than TN while being quite affordable.
It would have better colors and viewing angles than any cheap TN panel with LED backlight from Samsung, LG, and whatever.