Ah, I totally forgot about that. I have not read it (I did not buy Brief Cases). Thank you
Zoo Day in particular was really good. Kinda tells three stories in one that all take place simultaneously; what happens with Harry, what happens with Maggie, and what happens with Mouse.
The Mouse part is particularly illuminating, because it implies and outright states a whole bunch of things about Mouse that are almost completely absent from the main series—including some specifics about the way his power functions and what it can do. Not quite as earth-shattering character-wise as the Morgan freebie, but it does cast some new light on some particulars of the way Mouse operates in the main series.
Other than that, I don't think there are any new shorts in Brief Cases, just ones that I missed since I don't buy the collections when they come out 'cuz I'd only be buying them for Dresden. Probably not worth a full priced purchase if you only missed Zoo Day, but if you can find it cheap somewhere, it may be worth it.
I used an Audible credit to get the audiobook. I particularly liked Zoo Day because they switched narrators between perspectives. I think Mouse's narrator was Russian? I forget the accent. But he was pretty solid.
