This 3.5" display is transflective, meaning it both reflects light and uses a backlight making it viewable in a wide variety of lighting scenarios without needing a high-powered backlight.
This display also boasts high pixel density at 228 ppi - that means you can pack a ton of detail onto this display. Plus, with the option of using either 65k or 262k color over RGB (with SPI initialization) you'll have plenty of control over the color depth.
Further, this display offers wide viewing angles in all directions, so you don't have to worry about the angle the user will be viewing the display at.
This display really offers the best of all worlds - visible in most lighting situations, at just about any angle, and able to display a huge amount of detail - all with low power consumption.