I test drove the 2004 IS300 against a beautiful 2004 BMW 328ci (that I really wanted to love and buy). After driving both cars, I realized the IS300 was the much better car across the boards. Mechanically, the Lexus ran smooth and sound, with a lot more get-up and go. The BMW was sluggish and seemed to hesitate a lot more, with some choppy shifting between gears. I had been told by many people that the BMW would have more problems than the Lexus and in test-driving both, I had to concede that they were right. I bought the Lexus.
Interior is like a racecar and a fighter jet. It's very quick and maneuvers well. Very fun to "pilot" this car.
I wish it had a telescoping steering column adjustment.