I've got em on my rig (not the fogs). A little over $250 each, plus $23 each for pigtail adapters from 4wd.com. They cycle, which means that with close-up objects you may see some flicker. This can be fixed by having Ray at Rallylights build you a pair of dongles.
They're a great improvement over the stockers, but there are better combos out there in terms of illuminating distance at night (Daniel Stern lighting, and the JW Speakers in LED). I bought em mainly 'cause they're extremely resistant to temps, water, breakage, etc. I go to a lot of disaster sites (natural and otherwise) for work, and needed something sturdy.
Originally designed for use on military vehicles in Iraq and Afghanistan.
The only drawback to them is that they don't generate any heat, which can cause problems with ice and snow.
Below is a thread from Hilldweller's test of numerous lights (including the Truck Lites) on another forum. Since then, TL has released a newer version that is supposed to be much better...I think HD's still waiting to test a pair, though.
Headlight Shootout - JeepForum.com