Slow&rusty, The 400I was a great car, very usable, back seats, good sized trunk. It really was one of the best road cars I had, if not the best, very strong and good windshield wipers, two heaters that would keep all glass perfectly clear.
The car weighed 4,600 pounds, got 14MPG on the highway and a lot less in the city, held 17 quarts of oil and it was a wet sump engine!
The power was very nice ,liner, and turbine smooth.
I put over 20,000miles on that car in all kinds of weather.
I would still rather have my 930, which is also great road car with less maintence and more top speed and better handling, I do not like power steering and the 400/412 series cars have power steering and need it because of the weight.
911/930 have the best steering, good road feel with out the heavy effort.
My 930 is my road trip car now and I like it!