How does it compare to X3? I don't own that game either, but it's on my wishlist since I've seen people rave about it. Is one better than the other, or is each it's own separate thing?
No no no, "it's a 4X strategy game", not "a X4 strategy game"!
They're called "4X" in the sense of "eXpand, eXplore, eXploit, eXterminate" as in the basic rules of action you can use in such types of strategy games.
X4 is an entirely different thing, a first-person economic simulator and fleet/assets management title set in the namesake "X-Universe" sandbox. You personally fly your ships, from fighters to full carriers and capitals, or hire people to do it.
Also I forgot: space legs! Not particularly meaningful for anything, but walking down the ramp of your ship and seeing how fricking huge that thing is, always give a bit of satisfaction.
X3 Terran Conflict/Albion Prelude is probably still the most feature complete game of the series even without space legs, they're niche games and the learning curve is not a curve but a vertical line, but once you're in and it
clicks, you'll never get out.