Found this today, looks like it just got approved just 6 hours ago.

http://www.moddb.com/mods/designed-for-danger

Gonna give this ago later today, it looks promising! I like when people release things out of the blue like this!

Just finished it, even better than i expected... 9/10!

That was great, can't recommend it enough

Seriously, go play it, right now.

It's amazing, isn't it? I thought at first that it wouldn't have any custom content, but then I saw the first sign--Valve should make this a DLC!

It was pretty fun to play. Could've just put more effort to visuals.

But still, of course its worth playing!

I'm going to be the critic and say that it was okay. Not at all bad, but I can tell the mappack was a learning experience for the author, as the quality of the detailing rises the farther you progress. It isn't bad per se, just not excellent. Additionally, the puzzles were fairly underwhelming. I'm unsure if this is intentional, as the narrative implies that the chambers were made for adventure, not behavioral studying.

Anyways, now that I've said everything bad about the mod, I will say that the mappack is worth picking up for the humor alone. I would almost go as far to say that the turret knock-over scene was funnier than anything in the official campaign. Plus, the puzzles are worth a look and the mapping has some good ideas.

tl;dr: good, not excellent

This mappack was sparse with details at times, occasionally using the wrong metal textures and having a few big bland walls, but apart from these faults it was very well made. The plot alone could keep this mod afloat, even if it was uglier, and it's what truly sells it. The puzzles are occasionally a bit simple, but it's part of the charm in my opinion. The plot seems to have taken precedence over the puzzle in terms of what I liked best for me, which is a first for custom maps. Congrats!