They're too good and also bad at the same time. Most laypeople don't realize that "99.6%" accuracy is 1/250th chance of making an error. If you do inferences every second, that's 14.4 errors per hour. Now granted, some of those errors are false negatives, but I'm not sure what's worse in this case. Depending on which action is expected after receiving an alarm, this could render the device completely useless.