Op Anchorage is just a few linear missions with great loot at the end. Mothership Zeta is shit. You don't want to know the feeling when you've been playing through hours of tedious, bland corridors, and bullshit enemies only to hit a dead end where youre basically unprepared and under leveled to advance at all. All you get at the end is some Energy Weapons and maybe some gimmick outfits. Not worth it. The Pit is better. It has different missions depending on who you want to side with. The mutant enemies are terrifying and create some very tense moments. The environment is just fantastic. There are a lot of hidden, and secret areas that make the are interesting to explore. Unlike the other two DLC, you can actually revisit the pit whenever you want to access the traders or the ammo mill.