My parents have a VX II SS which was an ACT police car... This car was a special build from holden, as when they got it up on the computer, it had 'police build number xx"
I've ran new SS's, r33 skylines, 350z's and the most interesting run was against a normal ss commodore a mate had. Same model, everything, and i totally left him for dead.
Compared to other 5.7L commodores i've driven its much faster and louder as others have said. With the auto as well, you can hold it into the gear and it will not automatically shift even if locked in like most others do. Hence its pretty obvious it has an aftermarket computer.
The suspension in them is fairly good too... i cant drive the car to its full potiential, but it sure handles well. They also have cross drilled brakes on the front. And yes, thats how we purchased it. As well as the interior light, and digital speedo, and it also has 2km incriment increases, insted of the usually 10km.
Dayne