i own the stand alone version and actually considered buying the steam version as well to support the developers and steam downloads x-plane 11 ten times faster, x-plane is so much easier to manage, almost every addon is drag and drop with only a few installers, moving scenery around is a breeze, if you run out of space, you simply drag your scenery to another drive, create a shortcut where you put the scenery and just put the scenery shortcut in your custom scenery folder. plugin's, scenery,planes are all pretty much drag and drop. out of the 18 planes i own for x-plane 11 only one requires an installer which is the ixeg 737.I only use p3d for my pmdg and flight sim labs planes. with fsx-se still installed for the quality wings 787,146 and 757 still lagging behind.flight factor is coming out witth the a320 soon, can't wait for that one, x-plane has the best md80,757,767,a350 there is. the jar design a320 and a330 aren't bad to fly.there is a ton of free scenery and plugins, hd 4 mesh was just released for free for the majority of the world, almost everything from p3d there is something comparable in x-plane11.of course x-plane 11 supports native vr now. i will post some good links to some software for free and payware.active sky is actively working on a weather engine for x-plane 11 as well.i listed the flight factor a320, but it's not released yet, i posted what i own or suggested scenery, planes and plugins.
hope this list will help you get started, almost all scenery is free,but alot of payware developers are coming out of the woodwork.