I've got one coming and now one going.
I went out last weekend and did some playing after dark out in the desert testing the limits of the Xterra and doing my best to do wrong enough to get it stuck. I was unable to find sand loose enough to stop the SUV with the rear differential locked. I was able to work my way too close to boulders that I wasn't ready to yet crawl over.
I found backing in the dark a bit of a challenge as the stock backing lights are fine for the driveway or the mall but lack enough wattage for me. More power!
I looked around Target, Pep Boys and Autozone before finding these that I like. They're black, small, and have a broad foglight beam. They have adjustments which allow for them to twist a bit up/down and left/right to get them right.
I have a load basket and found that a piece of aluminum could be slipped down though the inside and outside basket supports. I bought one thick enough to just fit. Using a tiny pair of "U-bolts" I locked onto one of the wire posts and a pair of 3/8" bolts finished the mounting.
I couldn't deside up or down so went with up but can switch with a bit of work with a wrench.
The profile is pretty low, at least as low as the front mounted lights.
We don't grow trees here except in people's yards so I'm not really concerned about catching something and pulling the lights off. They will tip 180 degrees backwards with a bit of effort. I don't know if they'll break or move first.
I'll let them sit there for awhile to see if they grow on be before popping another hole in the roof and wiring these to a relay, a by-pass switch for in-town, and the stock backing lights.