There are a lot of reasons not to use dual cards. Besides having to buy two cards, you need a more powerful PSU than you'd need for one card, you need a more expensive motherboard that supports dual cards, and you're performance is still going to be limited by game support for dual cards. Plus if you wait too long, then the card your using even in SLI won't be all that powerful anymore. I think the time to SLI 950s passed long ago, if performance was your goal.
Having said that, if I really wanted lighting on something, I'd just buy the lights and add it myself. Those LEDs can be powered just as easily from the USB ports or some kind of lighting controller as they can by the videocard.