I'm always suspicious of LED room lights when they don't state the price upfront. They've been pretty price in the past, but the cost is dropping quickly. Some quick Googling found http://www.environmentallights.com/led-light-panels/ultra-th... which has 24" x 24" 17W panel for $250. That panel outputs 3000 lux == 3k lumens / sq meter = 1.1k lumens for 4 sq ft. This is the same as a 75W incandescent bulb. A standard 13W LED bulb is $16 for the same amount of light.

So the price needs to drop by about 1-2 orders of magnitude before these become practical for most people.