This may not help any, but I'm having the same problem with my Mystique. I can feel the vibration in all gears, but it's worse in 2nd and 3rd, at full throttle, when the rpm's are about 4-5 k. I've had the problem for a couple of months, but it seems to be gradually going away. Maybe I'm just getting used to it. I'ver tried changing tires front to rear, changing tires from the Mystique to the Contour, new driveaxles, new brake rotors, two motor mounts (roll restrictors)....I do have a very slight vibration when cruising, but it becomes much worse when I accelerate. I'ts also worse going uphill. Sound familiar?
