I have played a lot of FPS and other types of shooters, (just check out my games list or the hours I've racked up on CS:GO), but I can honestly say I've never played a game with the nail-biting action, graphics and hardcore intense realistic game play like I've seen with Insurgency.
This game really has it all for me and cultivates an atmosphere that keeps me (and my discerning GF) coming back for more over and over and over again. The team work that it promotes, the user community, (most) of the players (awesome and friendly) and the back and forth action between stealthy movement and tense exploring (in hunt especially) following by often brutal, but fair, firefights (except that damn RPG), that are like living breathing things. I have rarely felt so immersed in a game as I do with Insurgency and I don't think in the 30+ years of gaming that I've done that I've put in any where near this many hours. I was shocked when I realized that I'd eclipsed my time on CS:GO, but after a moment of thought, was not really surprised. CS:GO is a great game and so are a lot of the other military FPS style games, but I really feel that no one has done so much on such a limited budget and resource group as Insurgency as... and for SO LITTLE MONEY!
I have bought (through Steam and then Humble Bundle) no less than a dozen copies for friends and family to spread the goodness... and I'm a cheap old sod. :)
Go out, get a copy and jump in to the fight... and don't forget to say 'hi'.