I'm a Shadowrun GM, and my review will be from a GM's perspective. I nran the module as part of my home campaign, not in a dedicated Missions game. That is perfectly possible, making this a good buy for more than dedicated Missions players.
In my group, the adventure was very well received. It had the feel of an old module of 1st or 2nd Edition, with many stands to take, many moral decisions to make, but a very linear backbone. It was felt as a bit short, but that's the format. Mercurial went extremly well with the players, I had a couple pretty much squeeing about that NPC. MacCallister was well received too.
The adventure's structure is linear, but that's not too bad because there's not much reason to go astray. I had one scene whre I really had to improvise and make up a replacement for an important NPC, but that was easy to do. The pushing the Envelope pieces I almost all used, even though two slightly time shifted. Nazaire's introduction was a bit bumpy, but that's also due to the short timeframe Missions are meant for, I guess.
The art and maps were very well received, too. Especially the map of the underground. But the NPC pictures too.
Overall, this was one of the best canned adventures for SR I have run to date. It was fast paced, had a nice story and feel, and gave me as a GM pretty much all I needed without having to scour for things endlessly someplace or leaving me to deal with a mess. I could have, in the instance where my players managed to totally run from an opportunity, just let it be (that's what the adventure suggests), but I decided to introduce another interesting character from SRM04-01 instead (which I own but haven't played so far). Lots of fun with the locales - I'm starting to really look forweard to the underground book, and with that old-timey feel, a great addition to ongoing campaigns, or as a one-shot.
Bottom line: 5/5. You get much more than your money's worth out of this.
[5 of 5 Stars!]