There are plenty of manual Vel Satis' around - but none of them are six cylinders. The 3.5's are frightengly thirsty and heavy on tyres.
Mine has done 60k - was stopped by someone last week who was thinking about buying one. Quite honestly, I really like mine, so I didn't put him off. Drove from Newcastle to West Berks this pm at an average of 68mph and 39.1mpg. Not quite as comfy as my old Citroen CX's, but pretty damn good.
Problems? Not many, and all sorted under warranty. New speedo, flywheel
seal, clutch m/cyl, and that's it. One set of front discs and pads 10k ago. Still on the original rears. And I've just fitted it's 4th set of tyres.
Mind you, for peace of mind, I have extended the factory warranty to 5 yrs/100k miles.
Why are they so cheap? Easy. It's not a BMW, Audi or Merc. Same reason any other big car depreciates like a stone.