I don't understand why you don't want to run HDMI/DVI. Running digital video obviates most of the problems of long video runs, at least until you hit the real boundary, and then it just won't work at all. You mentioned unix drivers, but that shouldn't matter, unless you have some ancient video card that doesn't have digital out. Even so, they are cheap, and fully supported in most OSes. Just check the support in your OS before you get a new card.
I know I was kind of harsh about cheap crap, but if it's 1/20th the price, maybe it's worth a gamble. My USB-PS/2 adapters that look like they came from the same Chinese company turned out to not work, so that was a waste of $5 for me, but the blue cube delivery time was 5x as long, so it was worth a shot. What I really mean about not buying cheap crap is not to buy the stuff that seems to work, but introduces ghosts into the machine. Troubleshooting computers is the bane of my existence! ;-)