The storm has a pea, it is like an upside down regular pea whistle with a resonance chamber built around it.
There is more than decibel rating to how well or how far you can hear a whistle or how it will hurt your ears, the frequency and the trill have a lot to do with how effective a whistle can be as a signaling device.
In general pea whistles are easier to blow than pealess, you don't have to blow as hard to get a sound.
In general I feel that any of the following is fine as an emergency whistle and I don't think that there is a significant difference in performance between them:
Storm, Fox 40, Acme 2000, Acme 560, Acme 636, Acme 60.5, Acme 635.
My choice for EDC is usually an Acme 2000 with sides filed down for flatness or an Acme 636 which is small and flat to begin with, I often carry an Acme 560 because I like it much (strong, loud, easy to blow, talks well and I like the pea trill). For children I recommend the Acme 660, it is easy to blow, loud, inexpensive and comes in many colors.
Luis
Edited to add picture:
Click to enlarge
Edited again to comment (somewhat off topic):
After I took this picture I decided that my collection was a mess, whistles on lanyards hanging on carabiners on a coat hanger along with other stuff, no classification, no order. So I took them all down, off the lanyards and separated them into plastic bags classified as 1.- metal pea whistles, 2.- plastic pea whistles, 3.- Fox, 4.- Acme tornado, 5.- tubulars, 6.- cheapoes, 7.- others . I counted 131 whistles in total.