Hard to say, I've made 7 and 8 LED flashlight conversions, and even over driven them to get as bright as possible, but I've also made several Luxeon conversions, and well, if the Lux is properly focused (like in a 3D Mag Lite) there is no comparison to the outside 'throw' of the Lux light.
Don't get me wrong, Luxeons are great for outside, see down the road lighting, but I still think (and use) multi-LED lights inside to walk around at night.
Depends on the intended purpose. What do you want it to do = what it will do = happy customer; any changes to formula result in serious errors........