I used this car tonight and did the GT Championship. Golded all 5, but it kind of lumbered around, even fully lightened. At Cape Ring on the jump it almost lands on it's arse and tends to spin out on landing. It's gearing is very strange, massively torquey.
The tranistion between 1st and 2nd gear is way too long for a car of that performance level. That being said, it's a cadillac, so i cannot expect their supercar concept to be all the way there.