I test drove the 2011 panamera 4 twice - for some reason the steering doesn't feel tight at al, for a sports car. It is quite soft like my passat. My cayenne has a much tigher steering compared to this.

My other choice is the 550 which feels quite good - you feel the connection between the steering and the road. I tried the sport mode on the panamera and it didn't make much difference to the steering

Is my observation correct?

 

It depends on the "servotronic steering" option. With the option the steering is quite light, without it's much heavier and feels more normal in my opinion.