May 27th, 2015, 20:43
On my new (a year old now) system I have the boxed version of FSX installed in a C:\FSX folder right off the root instead of under \Program Files (x86). This was an attempt to defeat a security measure that was making a couple of aircraft unusable in Win8. Didn't work but I still have my RTM copy on the older WIN XP system I can fly them on. For the Steam version, it was automatically installed where all Steam programs reside, under C:\Program Files (x86)\Steam\SteamApps\common\FSX. The two co-exist on my system with no overlap and no conflicts. The Steam version is much more stable than the boxed version and Dovetail Games has already made a couple of update releases of improvements -- something that is never going to happen to the boxed version.