The only main difference is that the Gold version has the acceleration pack disc included. Not really worth buying unless you must fly off a carrier in an F18 Hornet
What is worth getting for Flight Sim if you ever think of upgrading is Nvidia 3D vision You need to have the right monitor running at 120Hz and you need the glasses and a decent Nvidia GPU and CPU.
Once you can fathom out the download sequence for Windows 7 it is really a big step forward. I have just got mine running after a lot of installation problems