During some of the parts that seemed completely impossible to get past without actually playing as if my life counted on it, I turned on the slow-mo and cluster bomb options.
I cried at the end when:
My main man Gaz took a round to the face. I didn't care too much about Price, although the mission where you play as a younger version of him was beyond words up until you had to run away. I was forced to use the slow-mo cheat since playing it 400 times isn't my idea of a good time.
I find it kind of odd that no one seems to really care that several thousand Marines were vaporized. Every post I've read in other forums seems to just skip right over that part and go straight to your SAS team and Griggs getting killed. I guess it cuts deeper since you got to know them, but that's still pretty cold.