My personal preference is to use the cool white for GI, with color matched inserts. Make sure to use non-ghosting leds (a little more expensive than the basics) for all your controlled lamps. I like the brightness of the 2SMDs for GI (not sure if that is a generic term or specifically nomenclature from Comet pinball). When I finished my first led job, I noticed all the led flickering and was worried that the strobing/flicker would ruin the game. After about 10-20 plays I no longer noticed it.