I have been looking myself The good ones are expensive. I got a quote for $720 for a Rigid that would fit in my front bumper. Really having to think about it for that price. I know there are much less expensive ones on Ebay, but I have also heard you really get what you pay for here.
The other part is I am pretty sure that they are sold as "off road" lights, meaning they are not street legal. I'd like to get one for my trips through Utah. There is one stretch of highway we drive at night 3-4 times per year that is open range, and the black cows like to hang out on the road.
I probably will end up with a light, just need to see a couple first hand to convince me it is worth the money.