Emerging wide-gamut displays, enabled mainly by LED-based LCDs, are capable of displaying a wider range of chromaticities than more typical gamuts, such as sRGB. Two types of LED-based LCD display products have been produced and marketed. RGB-LED-based LCD displays can potentially deliver more saturated primaries with use of the relatively narrow spectral width LEDs, while white-LED-based LCD displays might provide high brightness and contrast but less saturated images by using high efficiency LEDs in combination with the LCD-panel RGB filters. This results in a potential tradeoff between saturation and brightness. This paper uses color appearance concepts to examine two possible display-primary designs to address the question whether the decrease in saturation of the display can be offset by the increased luminance resulting in similar, or even improved colorfulness. The two display primary designs were mathematically simulated for visual assessment on an RGB-LED-based LCD display: one by adding a white backlight and one by adding a white channel on the LCD. The experimental results indicate that perceived colorfulness can be maintained, or slightly improved, through small additions of less saturated, but higher luminance primaries to a wide gamut display. However, more significant reductions in primary saturation cannot be overcome by increased luminance.