Simple but somewhat enjoyable game that doesn't overstay its welcome. That just means that the only challenge in the game is going through the campaign to unlock everything you need and to figure out in which order to build things and then you've basically mastered the game, since it's that simple and easy, but it's got pleasant enough graphics and entertains well enough for a few hours, and was only a few dollars on sale. The game is good enough for what it is and ends just as you start to realize that none of this design really makes sense and that everything could've been so much better with just a few tweaks.