Just got these from madcowdungbeetle I'd been following in an older post, Oct 25 2009
and here, Rock Sliders Sept 2 2013
As mentioned in the previous posts, these are very heavy duty, high quality and easy to install. The most time-consuming part was cleaning out the slag and welding seams inside the rear outrigger tubes. Had to go get a chisel set, <$10 at the new Harbor Freight less than 10 minutes away, and just chiselled away at the little pieces of slag that prevented the insertion of the rear slider tube. Once that was done the rest was a piece of cake. The height increase in stepping up is gonna take my 4'11" wife some getting used to but she's liking the D90 almost as much as I do.