I need a car with a very soft, comfortable ride, especially over bumpy or pothole-filled roads. I test drove a 2015 LT2 (9000 miles on the car) the other day on a bumpy road and thought it had a very smooth and comfortable ride. The 2LZ (28000 miles on the car) I drove later on a different bumpy road had a much nicer interior, but seemed to have a stiffer ride. The sales person at the dealership was unaware of any suspension differences, so I thought I'd ask the question here: is there a suspension difference between these two cars that would affect the ride? Which Impala version would have the softest, most forgiving ride and a quiet interior, too? Both cars had 19" all-season tires. The LT2 had the "Convenience Package," and the 2LZ had the "Comfort & Convenience Package." Thanks.