Like you say the physics works the same, but the model is operating in very different parameters. The inside wheel and Ackerman is always one big difference that stands out to me.

The theory about go stiff and low and aggressive on the diffs first then work towards soft and high etc should work. The theory I believe is that you get a quicker car working that way round as opposed to getting too comfortable with a car on the soft side of the usable spectrum.

One big difference is that it doesn't hurt when you crash a model car and you don't spend months getting the thing rebuilt to crash again.