The story is very well built and understandable - especially for those who have played and Peace Walker Snake Eater. The game graphics, power, background music and the difficulty are unmatched good and Hideo Kojima shows again that he is a visionary.
And now for the playing time. I got the story in 70 minutes by playing on easy difficulty, am several times died and did not all secondary objectives of the story followed, so much so. Furthermore, you have the opportunity to play missions after finishing the story even side missions, as well as the console exclusives. If you wanted to so will bring everything to 100%, you could come in my opinion, to a playing time of 5-6 hours. Compared: Metal Gear Rising: Revengeance has a playing time of around 3 hours in Speedrun one hour.