I like it, and I think I can answer why they are a staple in horror. The slow wind down in the music gives it a discordant sound, which has always been associated with horror in some way. Even more so if the music box is not working properly.
I was thinking about this and maybe a more representative test of temporal resolution test is a repetition of tones of the same pitch with gaps in between - At which point does the brain perceive the sound as a tone rather than a sequence of short tones? In the case of these sounds generated from multiple short tones, the difference in pitch probably accentuates the brain's ability to perceive that something is going on on a very short time scale. - I don't know, I am speculating... But this certainly is a very interesting series of sound experiments.
You should include in the description a link to the forum discussion. Also, here are 2 tags you should consider adding to all these sounds: Psychoacoustics temporal-resolution