I have 3 and 4 and they are both really fun, with 4 being better. Both were really good for their time. I liked the improvements 4 had from 3. And the courses in 4 especially are great, racing in the city or the dirt is pretty cool.
I have GT4. That game rocks. It had the best tracks I've ever seen in a racing simulation game. Although I didn't like the lack of Ferraris and Lambos.
Yea I was looking for some Ferraris but there were barely any. But despite that the car selection for the game was great, so many good cars to choose from and good diversity.
The Car List was poor. There were like 20 Skylines and 15 Lancers. There were still a lot of good cars, and the great track selection with Citta di Aria, Paris, Grand Canyon.