Cockpit view is the most realistic and therefore, in my opinion, the best. However, I wouldn't call the other views "cheating" because well, there are no rules that say you have to use any particular view. Also, cockpit view has the least (lowest) field of view. And actually, you could say, it has an unrealistically small field of view. You are basically driving with blinders on. In real life, you could turn you head to one side or another to make up for this, but not in GT... (I know, I know, you can press the look left/right buttons. but it's insane, I crash 100% of the time when I do this).