The couple I've heard about are all making great claims. There are so few in use though that it's tough to make a generalized statement. Let us know how yours works out. I know there will be a lot of interested people here on MR.
i know it has an initial high cost but factor in replacing halides every year, rising costs of utilities, the expense of running halides and keeping the tank cool .....chiller. i think it can pay for itself over the life, if it is what the manufactures make it out to be.
I am working with couple manufacturers to build me 10W Power LEDs samples. So packing couple hundred watts of LEDs will be much easier than the old days. Most aquarium LED lights are made of bulbs with clustered small LED diodes. These are mostly liquidated LEDs. The factories are phasing them out. For small applications, more picky customers would go for high flux, and the even more demanding customer will go for the power LEDs such as reef applications.