I'm not a fan of the Mongoose Flight from the Dark. In fact, of the Mongoose reissues I've read to date (books 1-5), The Caverns of Kalte was the only one I didn't consider worse than the original. Lots of edits just state the obvious, and there's one in The Chasm of Doom that attempts to fix an error from the original, but actually just changes it into a different mistake.
As for the mini-adventures in books 2 and beyond, the only one I've enjoyed is Vonotar's Web, from Kalte. A couple of the others have a decent premise, but the execution is sufficiently flawed to spoil my enjoyment.