Kasumi steals the crown for the best ME2 loyalty mission!
Stolen Memory has to be taken in the context for which it was so obviously intended. Not as simply a bonus mission. Nor as "The Further Adventures of Indiana Shepard", but as an extra character for your suicide team. And a bad-ass addition Kasumi is! You see this sexy and mysterious thief can turn invisible!
" A-ha!" I hear you say, " My Infiltrator Shepard can turn invisible!" Well, can your Shepard turn invisible, sneak up behind an enemy in a fire fight, stab that dude in the back and return to cover without a scratch? No? Well take that!
Aside from that cool ability, and a not-so-cool loyalty power which I won't spoil, Kasumi has, in my humble opinion, the best loyalty mission in the whole game. Without giving too much away think of an ultra sci-fi version of James Bond complete with the over-the-top villain, and final explosive confrontation which has a little dash of Matrix wire-work style action thrown in for good measure. On the down side, however, this character and mission work best in the context of playing through ME2's story. If, like me, you've finished the game several times (six in my case) and were looking for something to continue Shepard's adventures (as mentioned above) this is not it. I might have helped if the dialogue when recruiting Kasumi had detected that you'd defeated the Collectors, and changed accordingly. Shepard could have said something like, "Well you missed that, but I could still use you on my crew."
Having said that, it didn't really detract from the awesome nature of the mission, and I'd recommended playing through it a few times as there are a couple of ways to complete a certain task (one slightly more James Bond-ish that the other), a new weapon to find, and lots of fun dialogue from Kasumi including a great Planet of the Apes gag that had me laughing out loud!
Overall I'd give this a 5/5 because, as a loyalty mission in the main body of the Mass Effect 2 story, it is quite simple the best.
