Because ultimate ironclaw is a bigger waste of time as regular ironclaw was when released, I have not even gone into it.

1/ What do you think about the general difficulty level of Ultimate IMF and/or Ultimate FSC ?

Ultimate fsc is definately hardER than regular fsc. Regular fsc is do-able in full 2* gear, and easily clearable in full 4* gear (with no fsc experience at all).
Once you get experience and 5* gear it becomes a complete faceroll of a level. The new "Ultimate" fsc seems to be a "fixed" version of regular fsc (some of the silly safespots are taken away etc.) I actually find some of the rooms in ultimate fsc MUCH easier than their counterparts in regular fsc.

2/ How many revives did you use in Ultimate IMF and/or Ultimate FSC ?

I made it through d24+25 without taking damage my first time through, but I only got online for 20 minutes of the test. I cleared all of fsc and new vanaduke with 2 deaths my second time through when the test server came online again. If I were on a computer that got a constant 20+ fps I would not have died once for sure, as 90% of the damage I took was because of being under 5 fps or total game freezes ($400 laptop).

3/ Which areas do you feel could be improved ?

I think that every room in charred court should have increased difficulty from it's couterpart in regular fsc AND make every room have a party button that locks parties inside. The safespots and being able to leave the room while other people die inside it is just way too much of a free ride through the level. I also think there should be significantly more mobs in D26-27 other than zombies and slags. We need oilers to get their old speed/attacks and fire turrets to get their old range and randomness back. These things made oilers and fire puppies HUGE threats and putting some of them in rooms would increase the difficulty greatly. I would also like to see some more annoying/harder enemies added, such as curse develites and curse puppies in fsc. It would also be great if you could add some harder mini-bosses like trojans/slag guards who also use mage/missile attacks. I have plenty more ideas in mind about how to make a level that is actually challenging and therefore rewarding but I don't see them being put into place anyways so maybe I will post them in suggestions at a later time.

4/ If you feel like you've already mastered the current Tier 3, do you think the new content is challenging enough for you ?

This content is DEFINATELY not challenging enough for anybody who has mastered tier 3. I know some much less skilled players struggle a lot in regular fsc.

5/ (Special Question) Add anything you would like to tell them about here :)

ADD
NEW
CONTENT

Players want new gear, new items, new materials, new recipes, new monsters and HARDER new bosses!