As a kid, I thought this game was just a mere shoot and kill enemies for fun which was probably the reason why I haven't gotten past Act1 when I was young. But now as a teenager who's yet to become an adult, I realize the mechanics and playing the game is something that you shouldn't spend that much time on. The story is what is most important, you learn various things from all these kind of games. And most importantly the developers always find a way to touch your heart in a scene that seems so realistic yet it is 3D Modeled and displayed on a screen in a gaming system.
SPOILERS:
The amount of plot twists that are in the series is truly fascinating because at one point you may start to believe that one of the characters may be bad but in the end they turn out good or vice versa. This can be for example, Naomi Hunter. She was rescued by Otacon and Snake, fell in love at first sight with Otacon and then out of all the sudden she betrays them. But for a good cause to eventually lead them to victory, in my opinion I think Naomi shouldn't have died. Poor Otacon has already lost a lot of people and when Naomi recorded her final message that was displayed in the Patriots AI which also showed Otacon crying. It truly made me feel sad for the guy, i think he actually found happiness and then outta nowhere it just vanished because of war.
All the Easter eggs and flashbacks make it seem like MGS4 is really the last game in the series as they add so much referencing to the first game as if the series were going to be finished once the game launched in 2008.
I have nothing bad to say for this game, I am honest and I think it is a work of art, the storyline is spot on, the game engine is better than the older games and you can finally know the fate of some of the characters you have seen in the older games that played a significant part in the games.
In terms of the system, get a flawless working PLAYSTATION 3 to ensure you have the best experience. By that I mean make sure the game runs smooth and doesn't lag as it is very demanding. Use a good controller as well because you may need to make decisions carefully and you can't be getting random inputs outta nowhere when you are in the middle of battlefield like me.
10/10 I 100% recommend you playing this game, but play the series in chronological pattern (Start by MGS3) to understand everything correctly.