2006 Mercedes Benz S430 Handling Problems

Front end floats.
Doesn't track straight intermitantly.
Significant body roll, platform does not absorb dips and depressions which contributes to roll.

Back ground: Purchased as a MB certified vehicle on 11/27/07 from Ramano MB with 27610 miles on odometer.
Initial test drive revealed the car had front right out of balance condition. Mechanics attributed to a bent wheel. Romano switched wheels and tires (like new Goodyear Comfort Treads) with another S430. Salesperson said they balance tires and aligned car during pre-delivery prep. Car seemed ok during test drive. On way to home on interstate I noted car drifted to right and did not seem track right or hold the road. Had a follow up call from Romano and informed sale person of the problem. Sales person asked that I return it to the dealer to have them take a look at it.
04/14/08 (29209 miles). Returned to Romano as requested. Romano had no record of the car being aligned. Split the cost with Romano $182.22.
On way back to Binghamton I noted car still drifted to right had handling problems.
6/26/08 (29807 miles) Empire Motors replaced front struts under warranty and realigned $173.50. Handling problems persisted. Mechanic suggested that the tires may be cause.
4/8/09 (34523 miles) Replaced the tires with Michelin Primacy MX4 $785.44
Precision Automotive installed the tires and Hunter Road Force balanced $115.34. At that time they checked the alignment and found that the front end Camber was way out.
4/16/09 (34543 miles) Car was realigned with new Hunter Hawkeye alignment machine $105.45
Total spent to date $1,361.95 Total miles driven 6933.

Objectionable handling and ride characteristics:
When driving on an interstate the car travels along well for a mile or miles then the front end shifts to the right or left. The steering wheel is not being turned and is being held steady. At times I must reduce speed to minimize the roll and minimize the shifting of the front end. It's like flying in an airplane and continually having to trim the aircraft to keep it going in a straight line.
At times I've noticed when turning into a left sweeping bend in the road, the car wants to travel to the right, sometimes even when the crown of the road is on the high side it tends to want to push up and out into the right lane.
On a relatively smooth surface the car seems to react to every minor irregularity in the road. At 70 or 80 MPH a minor irregularities in the road surface sometimes translates into ones head rocking back and forth.
On a irregular city street surface the body rocks back and forth excessively like there is insufficient or no body roll control in the suspension.
For a relatively low profile heavy vehicle the car seems like its being buffeted by wind causing the car to rock.
When suspension setting is changed the suspension stiffening is minimal, roll is reduced slightly, but there is little or no suppression or dampening of the front end. When encountering a expansion joint or bump the shock and sound is significant.
Requested a MB factory rep. And or factory mechanic to come in and drive this car for 30 to 60 miles.
This car is not pleasure to drive and clearly it is not how a certified flagship S430 is supposed to handle.

A person with 20 years in the car business indicated that the ongoing handling problems documented since I purchased the vehicle maybe due to the fact that the vehicle may have been in an accident.

Your thoughts and advice will be appreciated.