GM transmissions are not good by any stretch of the imagination. They break - a lot, their shifting is erratic, at time smooth, other times rough, always protracted and never crisp, the Zf box is a definite upgrade in every way. Rolls used to have a reputation for awful reliability, that has faded, what has changed, BMW engines and ZF transmissions, bosch electrical, and zf power steering. The E-Class had the most upright seating of any car in it's class. The 300 looks too tall because the belt line is way too high on the car. The upright was to inflate leg room, which is good, but not really neccesary in a car with a 120" wheelbase. It's personal preference I guess, a commanding seating position is popular now, I'm just a fan of the low and in the thick of it position
porsche and BMW use, maybe it's just cause I'm tall, I don't know. I know rolls has gotten better since they started infusing german engineering (which is better than american engineering), and the belt-line on the 300 is too high and the windows are small.
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"The car is the closest we will ever come to creating something that is truly alive"
-Sir William Lyons