CS takes a while to actually take effect (ask your friends who've had to go through the gas mask stuff in military basic) as the crystals dissolve and release their evil magicks, whereas OC takes effect as soon as it comes in contact with a mucous membrane.
I don't know about you, but it doesn't do me any good if a bad guy suddenly gets all teary-eyed and runny-nosed when he's thirty seconds or a minute into beating my ass.
Get Pom. Compact, good range, and an innocuous-looking dispenser that doesn't draw a lot of attention when sitting in a pocket or on a keychain.
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