IMF - well, I couldn't run it well at all on normal server, so from the start this was a challenge on my framerate, though not as bad as what IMF was, surprisingly. The difficulty wasn't too much more than normal IMF, except mad bomber set meant I was on fire and electrocuted, A LOT. I prefer this to IMF T2 personally, and the twins look much cooler, but still not something I'd do alot.
FSC - Wow, just, WOW. Cursing zombies was a nightmare, especially when half my bombs were out of order, or I'd get cursed as I bring one up to charge, and get killed in the process. The levels are definately more engaging, and involve a bit more teamwork, not to mention the awesome(yet evil, god damn that was unexpected) difficulty ramp. Dissapointed that trojans were replaced with slag guards personally, but that's because I can't sit in a corner and watch the trojans tap away at my shield, but it's making me play a lot differently now, the new zombies having that shield on their back. (Psst, I hate it...)
I think if we didn't have over... a lot of mist, our team wouldn't have made it past the armory, or at least not cheaply anyway. However we did kind of abuse the unlimited energy, purposely killing ourselves between major stages to give us a fighting (read: struggling) chance against the seeming onslaught of curse breath, curse breath, Cootie being unable to do anything because fallen armor made her useless.
Overall, this new challenge should really give veteran, and skilled players a chance to prove that they can do it, however the token rewards (double that of normal) isn't really what i was hoping for, getting a blackened crest or whatever in half as many runs isn't really much use when you have it all already.
Okay, so I did this solo and i can say I'd never make it pass the first lvl in game. I would give up first before spending that much ce.
IMF - Fire and Shock are a deadly match, didn't realize what I was getting into and did this run with the wrong armor setup. Used Skolver + Barbarous Thorn Shield. Died many times getting to twins. Only real thing I hated was the respawning pup in the last area right before the twins. I can see this easy overcome with 4 people but with only 1 its suicide. Twins weren't that much harder and seem to fall faster than normal. I oops and died twice because I forgot to look out for those annoying robo pups. I also kept catching the corner by the switch.
FSC - Awesome redesign. Curse zombies are on a new lvl, love them. A question about curse, sometimes when i atk when I'm cursed it hurts me and other times it doesn't. Slag guards - Kinda disappointed they're not dropping hearts. I also noticed DA trick #1 doesn't work and like the new and improved pup room. Only made it to the end of the 3 floor before the testing server stopped. Also on the first floor you could skip the last button fight as the gate was down.