Kerbal Space Program version 1.0.2. I've been playing the early access game for over 2 years, but now that it became official I thought I'd write a review. My review is very positive. (But see the caveat about version 1.0 below at the bottom).
(Full disclosure: I don't work for SQUAD but I do help write one of the mods for the game, so I am personally invested in this.)
Get This Game. For once a sci-fi game that is actual sci-fi and not science fantasy. It doesn't insult the intelligence of the player, and it speculates what-if, in a relatively reasonable way, only breaking a few laws of physics here and there where needed for gameplay, rather than breaking ALL of them constantly like most space video games do.Kerbal Space Program as history
Although the solar system in the game is artificially smaller than would realistically be possible (so it doesn't take as long to get things done as it really would), it still has all the parts and the right places to emulate historical real-world space programs. Don't be fooled by the cute derpy-looking Kerbals - you can use the game to see what it would be like to emulate historical actual space missions - space stations in low orbit, docking maneuvers, performing an Apollo-style "Mun" landing, send rover probes to "Duna" (which is Mars-like), and so on. All from gluing together parts and having fun.
(And if you really want to go all-out, there are user community mods out there that replace the game's solar system with the real thing, so you can really try these missions out in full size).Kerbal Space Program as a 'tycoon' style game
If you like the old style 'tycoon' games where you have to come up with a means of keeping your business afloat and research new technologies to do interesting things as you move on to bigger and more ambitious projects, then Kerbal Space Program Career Mode is for you. Start up a new game, pick "career mode", set Normal or Easy difficulty (do NOT use Hard until you've played a while), and you'll have the fun of trying to balance funding (for making better space center buildings, and for making the rockets themselves), reputation (for making future offers you see be better for you), and science points (for buying your way up the tech tree). Accept contracts, and try to fufill them cheaply so your space agency makes money from them to fund the other stuff you want to do. Don't fail them or else you'll lose funds and rep for it.Kerbal Space Program as a mod platform
From it's early access days, a user community of modders has grown, such that you can do just about anything you can think of with the game. As of this writing, because KSP 1.0.2 is relatively new, some of those mods won't work just yet, but they will after only a week or two. If past use is anything to go by that's about how long it takes for the modders to catch up to a new release. As Steam is not the only means of obtaining the game, and not even the first means of obtaining it, the company, SQUAD, has chosen not to support Steam Workshop for mods due to the way it would open up the chance for people to make Steam-only mods that would be unfair to those who bought the game in its early days and supported the company before the game was even on Steam. I support this decision, but it does mean you'll have to take a few extra steps to find the mods and install them. Look up "KSP" on curse.com
and look for Kerbalstuff.com.
most mods are in both places.Kerbal Space Program as "edutainment"
The game is quite educational, but in that good sneaky fun way, where you don't realize you're learning - you're just trying to get stuff done in the game and in so doing learning stuff along the way. If you've got a teenager or pre-teen at home, give this to them. It does something that is really hard to do - it *demonstrates* though gameplay how a mathematical concept works, visually, without revealing the actual formulas, in such a way that the hard math can come *after* the intuitive understanding. Usually what makes math hard is that the understanding and 'feel' can't happen until *after* you understand the numbers. But here, it lets you play with the phenomenon first, and understand it later after its behavior has becomine intuitive to you, rather than the other way around.
Get. This. Game.A caveat:
My review refers to the 1.0.2 version of KSP and emphatically NOT to the 1.0 initial release that came out a week before and had a critical re-entry bug. Had I written the review about the 1.0 version, it would not have been as kind. The 1.0 release was rushed by about a week. The 1.0.2 release from a week later was MUCH better, and is probably what should have been the 1.0 release.
R.E. The KSP 1.0 re-entry bug: You may read reviews by people complaining about re-entry being broken when 1.0 game out. Those reviews weren't wrong *at the time* they were written. KSP 1.0 was rushed out with a re-entry bug that was very unfair, and importantly, really obvious so it's hard to imagine how they missed it. Adding a heat shield actually *caused* the ship to blow up on re-entry because adding it made the vessel flip nose-first, rendering the heat shield worse than useless as a part. If you see reviews complaining about this behavior, be aware that they are stale and referring to an old version.