The saw cost includes one 10" cartridge. I bought a couple extras
plus an 8" dado cartridge. I also happen to have one of the
preproduction cartridges. It works too. I don't plan to set any of
these off on purpose though.

The cost of a brake release is your blade (presuming it cannot be
restored by your friendly and competent neighborhood sharpening
service), the spent cartridge ($59), and maybe 10 minutes work.

General word has been that the blade is wasted, but that may not be
true. I have one of the stopped blades and its brake pawl hanging on
my wall (demo). There doesn't appear to be damage to any of the teeth
that aren't buried in the pawl. Several teeth are in the pawl. Even
if they are all wasted it would only cost $20 - $30 at my sharpening
service to have them replaced and the entire blade resharpened.