I just completed Chapter One.
Below are my thoughts on the plot, but be warned, spoilers.
I haven't ventured into Chapter Two yet because it already looks like it will not be worth it. Don't get me wrong, the game still hasn't lost it's charm for me and I'll still be playing it, especially with the supposed Online mode coming out (if I stop playing by then, that'll get me back into it, since it'll take a year for pc apparently.). Even though I haven't played a single other Metal Gear game except Ground Zeroes, I feel as though the ending to this game was a massive disappointment. I also feel like the roostertease "trailer" they play after you finish Chapter One was extremely unfair especially since the cutscenes they showcase are just stapled onto Chapter Two missions, which are basically Chapter One's but you 'can't use a buddy' or 'can't use reflex time' or something. I will give the entire thing credit though, it took me around 30 hours just to complete Chapter One.
I really think that there was extreme potential for a Chapter Two especially knowing the cut content, and I really hope they, in the future, decide to work on it.
Meanwhile, the game is actually pretty cool to do
this in. (spoiler free)