Hepco & Becker
I have German made Hepco & Becker engine crash bars on my XT600E, and they lok much more usefull than the ones on your link. These come part way ariund the sides of the crank cases.
I would have prefered them to have had an additional attachment point on each side to stop hem folding in and hiting the crank case in the event of a spill, so I had a cuple of brackts welded to the motorcycle frame and had cross braces made. I then mounted home made jerry can holders and 10 liter cans to them and rode 35 ooo milles without problems with them, including a few spills.