If you enjoy good stories and can forgive some rough mechanics, Kane & Lynch may be worth your while.
K&L is a mature game in many ways. Not only it shows profanity, violence, drugs, and what not; there isn't a motivation in this game that isn't selfish, and you'll be doing nothing at all that leads to a better world. Everything you do, you do for selfish (and unlawful) motivations. Not to mention you play the role of a despicable guy to begin with -and one that is rather unrepentant, too (his only regret is even selfish in some ways).
By mature I not only mean there are mature topics such as extreme violence, drugs, and much more. By mature I mean the story is told as-is, no moral judgements, no anesthesics involved, full color graphics included; and, most important, it is told with zero fantastic elements and little to no narrator tricks. Suspension of disbelief is kept at its bare minimum, which is a rare achievement these days. There are no cheap turn-of-the-screws, no morals, and no holding punches back. This is a story that could very well be put into film and would appeal to a wide array of audiences -while carrying itself some reminiscences of action movies.
The crook-buddy-movie story not only is a real treat; it is nicely told both via stylish cinematics and ingame dialog. There's a lot of swearing, granted; but that swearing is only fitting given the game's premises and its protagonists. Very seldom (if ever) does it stick out as unfitting.
The main campaign (which can be played in split-screen coop, hence I refrain from calling it "single player") has some of the most daring -and fun- levels I've ever seen. It's not just about variety -which it has, and in spades: it's the blend of the story, characters, unique environments, and some jaw-dropping plot twists, sprinkled with a good dose of dark humor.
Within K&L proposition there are some design choices many critics found irksome. Take the shooting. Shooting isn't inaccurate by any stretch of the word. Shooting in Brothers in Arms is way tougher than in K&L; however, people expect K&L shooting elements to behave like Crysis or CoD. That isn't the case, but that doesn't have to be bad. That said, controls (especially cover) can be bothersome. I experienced some weird bugs using keyboard and mouse control scheme, like having to stop doing anything else to bring up the minimap pointing at the next checkpoint. Also, there's the the inability to configure anything different than a Xbox360 controller; I have a Logitech Rumblepad 2 and I would love to play K&L with it, but I can't. I know there is an Xbox controller emulator out there but it implies some tweaking I'm not willing to do.
Without delving too much into technical details, it is fair to say that K&L sports some richly detailed character models (many of them looking better than those from recent AAA titles such as Dragon Age, and definitely ahead of those of GTA IV, for instance), but the environments and some vehicles can look bland. The AI could certainly be better, but facepalms because of their stupidity will be few and far between.
All in all, K&L is the kind of game the industry needs: a unique proposition that is innovative, bold and daring, but one that keeps fun at its core as well. K&L constitutes a clearly distinct offering that caters to mature audiences like few other titles ever did, while appealing to certain shooter fans all the same. Its design choices might not be ideal for many players, but that comes with the whole package of any game with such a strong personality. With K&L 2: Dog Days coming out soon, K&L: Dead Men has undergone a drop in price and it might be worth your while to give it a try. If you enjoy good stories with memorable situations and characters, like more realistic shooters, and can forgive some of the rough mechanics, you certainly will be glad you did. I, for one, certainly am.