Originally Posted by Skybird

Complexity of FSX addons, both scenery and cockpits, has gone much higher now than in FS9, with the new PMDG 777 apparently being the new king on the hill (I have not tried it so far). In the early years, FS9 had the edge over FSX in IFR, with FSX being superior in VFR. But that gap in IFR has reversed, FSX now has the lead in that field. For that reaosn, the really complex aircraft addons no longer are done for FS9, it just cannot support their needs in software preconditions (not to mention hardware demands).

Regarding flight physics and simulation of the air and how especially small planes behave in it, FSX is better. FS9 is too undynamic there. I don't say FSX does it fully realistically, but it is much better than FS9.

If hardware sets limits, there is nothing wrong in staying with FS9 if it is stable, I did the change from 9 to X years late myself. Once the hardware is there that can support FSX, there is no argument anymore to install FS9. If one does not plan many addons and stuff, I would maybe go with P3D 2.0 (maybe one wins stability and some frames, at worse you gain nothing, but also do not get hurt). If addons, especially PMDG and aircraft stuff, is a must, I would stay with FSX currently.

Too bad that bringing P3D to 64Bit (no memory limit then anymore) is so extremely stellar a project (all addons would need to be made compatible if they should run in it), and unlikely to happen. Of course true multicore support would be welcomed, too. But also, currently no plans for that, it seems. Too bad. As PMDG indicated, the legal licensing issues also are anything but minor. I once had higher hopes for P3D.