I tried for the 5/7 day survivor once, and barely got past hour ten. I'd still like to unlock the laser sword, but I simply don't have 10 consecutive hours to devote to playing a game anymore. Just one save slot would have made a world of difference for those two achievements.
Is Full Set the one for meeting all the survivors in your notebook? If so, I believe it carries over between games, so that you can just concentrate on locating the survivors you missed on previous playthroughs.
I was well on my way to getting the Saint achievement when one of my stupid survivors decided to lead a mutiny and take off with a bunch of people I'd already saved. Next time, I'll be sure to always have a bottle of wine in my inventory.
Transmissionary was just stupid. Glad I never bothered trying for that one.