Metal Gear Solid V: Ground Zeroes can be quite short, especially if you do a speed run of the game without caring for side mission content, and since the game is already out there despite the fact that we’re four day away from release, the first speed run videos are being posted on the Chinese YouTube knockoff Youku.
And they are... quick.
Depending on where you live, the video embeds at time load very slowly or show loading errors because they're streamed from China. In which case the direct links often work better. Reloading also may help.
Quite obviously, before you watch the videos, you must be warned (if the headline wasn't enough) that they spoil the whole story of game, besides the side missions. Watch them at your own risk.