I love it! A bit congested, but it works. Having soldiers that already have certain skills/equipment should of made it an easy DLC, and it kind of still is, but the besiege/threat level seems to happen pretty frequently the more you play. TBH I am only about 3 hours or so in, but I already lost a favorite soldier (and consequentially, a mission I believe...). Have yet to travel into a danger zone too, but i will very soon to see how long I can survive.
If anything, I'm the most upset at not being able to use my existing MS store buck on the 360 store like I have been already (full games and DLC). No matter, still double dipping!
Edit: MS bucks finally worked... but damn this game. I lost ANOTHER semi-important guy-quest giver to a siege! Shit's out of hand... but it feels so good.