From Day-one owner, Comes an honest Review, the only one here that actually deserves a '10' rating.
Onwards....
Learning Curve - I'd like to say that to get a grip for the game it would take 1-2 hours. A very entertaining 1-2 hours indeed. Its not a bad thing either because you slowly learn the tricks of the trade and end up remembering, "Hah! Who's got Good Lines Now?" You start off with Slow cars and before you know it, your Overtaking Ford GTs in your GT1.
Difficulty - Just Right. I mean the Difficulty ranges from Steel to Platinum. I completed the game on Steel pretty easily. Silver was a step up, and mildly challenging. Let's just say, for an amateur racer, im still battling all Gold. There are about 100 races in the main mode alone so you'll never get bored.
Time Spent - Around 400 hours until my Xbox Died. I AM NOT A FAN-BOY.
Gameplay - Over 100 cars, I assume 80 tracks, Some of the greatest modes around; overtake, cone challenge, 2 LAPS ON THE 'RING! and more. Kept me hooked, why not you? The controls are great; for the whiners that say the steering is stiff, well, its called reality really....
Graphics - I personally think the graphics are stunning, I love watching the Fly-bys of the cities and I'm not much of a whiny-crying-baby- nitpicker so I consider the city AWESOME and the cars STUNNING.
Sound - Oh the beloved Engine sounds. Look back on Your Porsche GT1 and it sounds like a freaking JET TAKING OFF! And the engine sounds all sound realistic. Not to forget the 100+ song soundtrack!
Value - Since It's part of the 10$ Microsoft Program, im tempted to go out and buy a second, or third or fourth copy to just show you how amazing it is.
Tilt - BUY IT; NOW!
Warning - since this is a personal review; I have come across snobby "Wh3r3s teh littl3 GT4 Logo?" people who hate it because they're using an Xbox controller and it doesnt say NFS or GT4 or doesnt have a boost meter in it. Get what kind of game it is through your head first, and remember, real racing games dont have 'PRESS X ON YOUR CONTROLLER TO ACTIVATE NOS AND SWOOOOOOOSHHHHHHHHHH YOU FORWARD'.
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Have fun =)!