I prefer a simulator therefore Gran Turismo is more suited for this. GT5 was far from perfect or meting expectations, but it is superior to Forza 3 in most ways (Sheer amount of content, graphics, online, polyphonics dedication to patching and adding to the game post-release). A better comparison will be when Forze 4 is released later this year (could be a whole new ball game).
PSN: Saugeen-Uwo Feel free to add me (put Vg Chartz as MSG)!
Nintendo Network ID: Saugeen-Uwo