Okay you fly helis so you have good coordination. That will really help when it comes to flying bigger planes than what you been messing about with. BUT ... one thing you may not be ready for in a scale plane such as the P51 is knowing how to land her without stalling. In the sim its a perfect environment, sometimes no wind at all, trims are perfect, no dead stick etc. In real life there is also the pucker factor, money money money ...

I will not believe that a sim is like the real thing ... it will not be at present. If you really think it is then sorry to say you are only deceiving yourself. When I started on a sim I could not land it right, I will always do the Kangaroo Hop ... but in real life I can grease it in. On a sim I can fly a heli pretty decently, in real life you gotta be kidding me!

Without experience on smaller planes you may just stall her on landing, warbirds have a relatively higher wong loading compared to an aerobatic plane. Flaps are your friend and unless you are familiar, it may end up as a pile of match sticks. Still it does not mean you cannot but its a risk ...