Who would ever imagine I will support something FordGT said?
Of course, difference in physics was huge under one *small* prerequisite: usage of Simulation physics setting. Shame nobody wanted to touch it with 11-foot pole, especially Turn10 - who didn't even bother to highlight its very existence to FM4 players or even to enforce it through Leaderboards, Rival or Matchmaking.
Also, usage of 900-wheel in conjecture with Simulation physics was Godlike Physics Mode of FM4, shame so small amount of players had a chance to experience it.