Would you sell your wife, dog, car, house and kidney for add-ons? - FSX
Do you, once in a while, have the urge to punch Microsoft's programmers in the face? Hate being mainstream? - X-Plane 10
Got a degree in computer science or want to get one? - FlightGear
Prefer flying in the web 2.0 age? - Flight!
Really, really, REALLY like Switzerland? - Aerofly FS
You've certainly got magazine subscriptions. Want one for a flight simulator? - Prepar3D
All provided you've got a computer that isn't geriatric (i.e. 2+ CPU cores with 2.5 GHz+ each).
If not, ask yourself the above questions, but go back a step in version numbering, i.e. FS9, XP9. (The others don't count.)
+2, With the exception that I believe it a bit unfair to call out FSX for add-ons vs XPX. At the end of the day the XPX stock hanger feels more incomplete to me as it ships out of the box, thus it still needs add-ons to be better rounded out. Plus, eyeballing it, it seems many of the top-shelf addon's for XPX aren't up to par with top shelf FSX add-ons. XPX fans would defend by pointing out XPX just launched. FSX fans could counter that's because XPX is a generation late to the party.
Finally, XPX costs $80, FSX GOld (includes the Acceleration exp-pack) is $30. If you equate the budgets, that gives you some extra spending cash out of the gate to put toward add-on's. If you like combat sims (such as DCS) you're first Add-on is a no-brainer: The
DCS VRS Superbug (soon to get some teeth with the Tacpack). There's some fantastic (and free!!!) carriers out there too to fly it off of.
In fact, shut-up, stop reading this, and go buy it.
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My Rig:AMD Phenom X4 955 Black Edition OCed@4.0 GHz/GIGABYTE GA-890FXA-UD5 AM3 AMD 890FX Mobo\ MSi AMD 6950 2GB \ 8 Gigs of G.skills Ram\Storage: OCZ SSD 240GB/ Bunch of HDDs\All held together by: Coolermaster HAF 932 case
Other Assets Deployed:
HOTAS:
Logitech G940 
CH FighterStick/Pro-Throttle/Throttle Quad/Saitek Combat Rudder Pedals
TrackIR
Simpit: ETA Q2 2013
Wheel: ETA Q4 2013