billwhite is entirely correct. Flight Simulator (9 and X) is a fantastic package which allows us to emulate real flight in our homes in a very realistic simulation of flight, with real-world locations and geography, real-world aircraft, and real-world flight dynamics. For what it is, at its price, it is fantastic.
FS9 is what it is - and we who use it improve it with various add-ons, both freeware and payware. For many of us who have major investments in upgrading our FS9's this way, it would be a "downgrade" for us to abandon FS9 and start with FSX. We would have to spend a lot of money all over again buying add-ons for FSX to increase the realism factor. For me, that's never going to happen. FS9, with all my improvements, is just fine for me. For me to consider upgrading to a new flight simulator, the realism factor of the new offering would have to be a giant leap from where FS9 and X are now.
Improve what you have, and enjoy!
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