This is a wonderful little toolkit for building your own megadungeon, and I can say from personal experience that it works really well at the table to generate a dungeon on-the-fly. Some caveats: I would recommend reading the whole thing through first and being very familiar with the material. Also, there is a really nifty "roll all the dice" mechanic to generate each room, and that eliminates the problem of rolling on multiple tables. However, I would highly recommend using different brightly-coloured dice to make reading the results as smooth as possible.

From experience, it also helps to tell the players that the dungeon is randomly-generated ahead of time. Also: There is a great "snakes and ladders" worksheet that helps generate different-flavoured environments within the dungeon. I would print that out and put it in front of the players, so they can see the mechanics at work. It means breaking immersion slightly, but I believe it's worth it; showing players what's going on "under the hood" adds to the excitement at the table, and makes it clear that both the DM and the party are exploring the castle together.

Castle Gargantua has a very distinctive grim (Grimm?) gothic fairytale feel to it. It also makes reference to real-world locations and characters (e.g. the Duke of Parma, the Crucifixtion of Jesus(!), etc.). It's fairly trivial to strip that all that out and reskin it, however, and even the size of the dungeon could be modified relatively easily (just count each square as being 10 feet instead of 60 feet, and ignore all the stuff about gigantic enemies and furniture). However, it's obvious that Castle Gargantua would work best "out-of-the-box" in Lamentations of the Flame Princess, with the setting assumption of a pseudo-historical 16th century Europe. Nevertheless, as I said, it would be pretty trivial to run it in any old-school system, in any fantasy setting.

Finally, Castle Gargantua can be used away from the table to generate a dungeon room-by-room ahead of time, helping the DM to design the dungeon themselves. Seasoned DMs may not need this kind of structure, but novices will learn a great deal by going through the book this way. And the castle itself is so flavourful and distinctive that even an experience DM might appreciate chanelling their creativity through ideas that Castle Gargantua brings to the table.

If you're looking to add a little extra verisimilitude (and tons of gory details) to your roleplaying combat then Trauma's definitely the book for you. It's written with the developer's own "Fantasy Dice" system in mind, but can be adapted to any other system with relative ease (and there are notes on the Radical Approach website for conversion to some common systems, including D20, GURPs, and World of Darkness).

There's a huge amount of information crammed into the book's 189 pages, so it's easy to get overwhelmed if you're not careful. I recommend picking and choosing only the parts you want to include in your game rather than trying to adopt absolutely everything (unless you're of a particularly simulationist bent). Surviving a brutal fight with a dozen orcs only to die of gangrene a couple days later might be medically accurate, but is probably going to be unsatisfying for your players (again, unless they signed up for a really hardcore simulation). Still, used with moderation, it's an excellent resource not just as a wound system but also to give you ideas for descriptions during and after combat. There is also enough colourful flavour text to avoid it becoming an overly dry medical textbook. I would definitely recommend picking it up!