Maurizio, i have played GT5 and was not impressed, Forza 4 on XBOX 360 is IMO better, it is out next week and the demo is available now for download and it is brilliant, plus the Granurismo S is going to be on there too.
I was always a Playstation person, had a PS1, PS1 Slim, PS2, PS2 Slim, bought an XBOX because at the time, the PS3 was £400 and i payed £210 for the Xbox. Forza is king of driving games IMO.
Love GT5....Just do not get enough time to play it.............The only thing I think is a waste of time is the mode where you aren't driving the car...You have a driver a tell him how fast you go......Don't get it and it bores me.........Other than that love it.