You can fly it, that's not going to be a problem and the g4 dose pretty good.

It's the landing approch for any sims, not so much the ground handling.
None. Not for landings. It dosn't tip stall and just do a gentle nose dive.
You can hold insane AOA at low speed and it'll still land like a kitten
Your real mustang is not going to be perfeclty tune/built or tune like in the sim or G4.
Your not going to have air speed readings or auto zoom, so you might as will trun all those features off.

You might want to ease your way in with other low wing models, such as a clipped wing 4*.
It's gental enough to allow you many, many practice touch and go in real life . And also get you more
familar with your real flying site. You still need landmarks to help guide you. This is where the G4 comes
in handy. You can build a 3D field simular to your real flying site. You be able to have more stick time
doing straight fly by over the runway or practice doing a victory roll.

Then many move the CG back after you get comfortable with the 4*. Maybe even add weight to make it a brick so you'll learn to
come in hotter on landing approch.

Or just get an arf with tappered wing. Plenty of .40 size mustange arf on the market.

Your mustang model will also nose over more on rough fields.