It's nearly impossible to review this game objectively. Then follow the readme to install the game. To install Garry's Mod, make sure you have Steam and Half Life 2 installed. While I could list a ton of the most well known games ever that came from this engine, there's nothing that exemplifies its great strength than Garry's Mod.
The Half Life engine is one of the most robust out there, able to support a ton of different games and genres.
