Overall, my experience with this car has been positive. It looks good, handles well, and has plenty of power. My one complaint is the car seems to rev too high during hard acceleration. I know of another Diamante owner and he made the same comment.
Though I am generally happy with this car, my research into this vehicle has given me some evidence of reviewer bias when it comes to Japanese cars. The generally excellent reviews on the Diamante referred to the excellent performance, handling, amenities and so on. My wife has a 1999 Mercury Grand Marquis and that car received mediocre reviews from the automotive press. However, in the opinion of this reviewer and someone who has driven both cars regularly, in almost every category, the Marquis is a better car. It is more comfortable, has nearly as much power as the Diamante, has traction control which the Diamante does not, a much better tuned transmission, and a host of other nice little features such as a compass that the Diamante lacks. The only category that the Diamante might win out is handling, but that is not by much. The point is, if you are considering buying this car or any Japanese cars, read the reviews from the automotive press with a small dose of skepticism. They are certainly good cars, but, I think the declared differences in quality and performance between the Japanese cars and others is sometimes exaggerated.