First, the gentleman who described the STS-V's handling as "sloppy" is way off. As a driver of stock cars, open wheel racers and, currently, shifter karts, I assure you that the STS-V has enough handling to accomplish any manuever that could sanely be attempted on public roads. This car is nicely placed 80% of the way between an M5 and a Jag R-type. It is a tad softer than the German cars, but that's more than acceptable to me--if I want to get beat up by a stiff ride, I might as well go to a race track and drive something really fast. This is the car that persuaded me to get rid of my old BMW 750. No 5 series or E class car was able to do that.
Motor, baby, motor! The steering is pretty much perfect for a street car. The interior fit/finish/materials are right up there with the best imports.
The brakes are too touchy. This isn't so much related to the amount of assist as to the master cylinder being too large--there isn't enough pedal movement to allow correct modulation. The hieroglyphics used on the various controls are confusing. The passenger foot well is too small.