Having run it:
This mission is balls hard. I ran it at Origins and had a table with 6 players from 60-250 karma, probably around 125 or so on average. I also warned them up front that the mission was really dangerous and to play smart. By the end of the mission, one character had burned permanent edge, several were near death, and about half the party was held up by sustained Heal spells and drugs.
The major problem is that if your players don't realize how bug spirits actually fight, and they don't ask a contact for advice (or don't get the right advice), they are enormously screwed. I'm specifically referring to Fear - if the runners don't have a good counter to being Feared, most teams won't have a chance in the final fight unless the bugs fight very stupidly. Willy really, really should advise them to carry some Guts; supposedly he knows about how to fight bug spirits, and it's surprising he knows about KE-IV (which is nifty, but not vital) but not the importance of having a counter to Fear.
Even with Guts, the last fight is no joke - a pile of spirits (with 6 edge each, since they don't use group edge, and counterspelling 6 which they can teamwork for spell defense) can really mess a team up, but the runners have a fair chance.
On the whole, I thought the mission was good. I really noticed a difference in quality, presentation, and editing from S2-S3 missions (this is the first S4 one I ran). The art, too.
My complaints:
-Willy really should warn the PCs to prepare for Fear (if they hadn't called MacCallister for better advice, the final fight would have been a really anticlimactic event in which everyone gets chain-Feared).
-The timer on the queen is far too long. Shadowrun fights don't last 6 combat turns. If she gets summoned, it's going to be because the PCs ran away, got chain-feared away, or lost. I'd rather see the timer be much shorter (maybe 2 combat turns), have some rules to allow the PCs to figure out how little time they have, and make the frenzy on the insect spirits weaker (maybe give them +2 to attacks and -2 defense) so that the queen actually has a chance of appearing and getting away or being killed by the PCs.