To be honest, there are many things that both PD and T10 are good at and bad at. To start off with, If anyone has ever watched a hot lap video of both Gran Turismo 5 and Forza 4 at Le Mans and say in LMP's (it doesnt have to be the same matched time and car and what not. It is just a driving comparison at high speed) You can easily pick out things from both titles that you like and hate.
From my perspective when I watch a GT gameplay, this is what I like:
Accurate Rumble strip sounds
Accurate Tire sqeal sounds (talking about a quick 1- 1.5 second tire lock up. Not including drifft)
Less road imperfections
Proper aerodynamic simulation of wind passing by camera (right after spec 2.0 I felt as if they ruined it but i noticed how much more accurate it is)
Accurate scenery from the time period scanned
Now this is what I like from Forza:
Detailed scenery objects
Defending AI
Cars are properly placed to race each other
What I dont like from a GT video:
How fast one can pass all the AI no matter how "skilled" of a driver you are in the game or reality. It is relatively easy to stay off the grass and pass slower AI.
Rabbit leader
Poor car classes versus eachother
What I dont like from a Forza video:
Poor car handling (they act as if they're on ice and snap every 2 feet)
Poor aerodynamic sound simulation
Woobling of the camera (to a degree it is good but it is an overdone feature)
SCREAHING TIRES THAT HAVE NO CHANGE IN SOUNDS WITH RELATION TO SPEED
Woodpecker rumble strip sounds
Basically to me, all the little things in GT add up to make it one of the most superior console racing games there is, with the ability to be criticized next to some PC games. Of course the driving is a big part and I've always thought they have hit the nail on the head with their physics. However the GT6 Demo felt different but somehow better. I could feel the aerodynamics actual working and going over the car when i went in to take turns through silverstone. However it has been a LONG while since we have all played any GT6 build and im sure the physics have been toned to almost perfection.
Now talking about forza, they have hit the nail on the head with details. I'll give them that to a degree. A tree looks like a tree, metalic paint looks like metalic paint (but gloss should never look white under the sun. That is the only place they messed up on paint), pavement looks like pavement, tires look alright, and carbon fiber looks like carbon fiber. Smog in the air at sebring looks real with the dying sunset but still has that perfect colorization. I just cant describe their graphics engine, it looks too good.
But, what they lack is proper simulation of driving. I feel as if when i drive on forza, it is no different than that of Real Racing 3 for my iPad. The cars dont turn and hold the direction i want them to go, as they have some sort of issue with bouncing back 5-10 degrees from where i last turned the wheel. The issue with 3rd person driving could simply be fixed, if they stopped it from pivoting around the car and left it in a locked position. That is probably one the largest problems with 4 and 5 which make it such an acrade feeling game. Interior details are stunning, but some are overdone and overexagerated. My synopsis would be I would buy the game if it let me control features that I could in a microsoft flight simulator.
And that's where i think i'll leave off on this monstorous post. Which is, if this is to be a simulator, let the community fiddle with the options. In MFS (Microsoft Flight Simulator) there are soo many options which I can set myself to fit my personal likes. Sure it's alright to design a game meant for people who love cars, but maybe allowing the ability to modify a users own personal likes would boost the enjoyment for the game. Now im sure people will respond to that statement as there are too many things which can be edited, taking too long to cover each one, or that it would be a waste so I just want them to add more cars. Well this is GTPlanet, the largest dedicated website to anything from what i've read. So give that responsibility up to us. Allow moderators to approve these customizations for the communtiy as set by GT community guidlines. Something that will allow us to put in Freeware that can be used to enhance the game. Because Microsoft Flight Simulator is really a boring sim with out doing the things you like. Flying your most favored airline or best WW2 dogfighter makes you enjoy the game a lot longer. That is something i think they should look at.
So on the Main point of things. GT focues on the smaller points to really make it a great game. Forza focuses on all the large aspects of the game which take half a second to notice. After you have found them all the game gets stale, and you try to do new things. Eventually you'll run out, and go back to the basics. Racing