Nope I kid you not.
What do you think this is? It's DCS. This mustang was done on a lark by a couple of guys, well before any other ww2 modules were even conceived.
Thus, you need to wait for your new mustang.
Furthermore if you really don't think you stand a chance in the current mustang you need more practice. Learn to fly it right and you'll succeed, but nothing is going to change the fact that planes like the 109 are more heavily armed, much lighter, more powerful, climb better and turn better at certain speeds.