From my perspective, I think if you have a PC rig with a nice setup that can run some of these great PC sims, why lower yourself to mess with Forza and us great, unwashed console-only masses?
That said, as to Forza I actually prefer running the lower-class cars, because I like running with friendly gamers from DSP and friends, and the lower-end cars tend to allow a greater percentage of the people on my friend list to feel competitive and have fun.
I was very disappointed with PGR3 in large part bacause they excised those personality-filled, lower end car classes. Those classes had always been the mainstay of our PGR2 poker night racing, and inevitably most of the real, competitive fun was in those lower classes. Forza didn't stick well enough here over the long haul for us to get anywhere near the purpose built racers in our get-togethers, but some of that had to do with the depth and variety of cars in the lower three or four classes. Some of it also had to do with the attrition among DSP gamers as you climbed up the class ladder, just due to offline gaming time.
The 360 is a starved system for racing. It also posesses an amazing potential to provide great racing games, from the controller to the official FF wheel, to the online possibilities, maybe even a party system. I am disappointed that Forza is, well, Forza, and has all the well-known quirks and flaws that we all know to expect. I am very disappointed that you can only run 8 cars per race, and am worried about end-of-race BS ruining any chance at running the long races I like to run (where the Forza engine really shows it's strengths, too). But, I think Forza is a quality game, and I am very much looking forward to its arrival. There are plenty of flaws to the Forza philosophy, but hey, there are a hell of a lot more positives than that, and personally, I think anyone here who has a 360 would be silly to skip the potentially great DSP poker night crazy-fun-times even if they only enjoy it for a few weeks and then sell off the game and return to their lonely, voice-free, tweakathologies on the PC

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