My wife used to carry pepper spray when she was in a non-gun zone. This one was highly rated:
All the units in the Five Point Three® line contain our famous 2% formula using 5.3 million Scoville Heat Units (SHU) OC pepper. This is one of the only true Police Strength pepper sprays on the market, and the original legacy formula that is carried by police, correctional officers and the...
foxlabs.com
I'm sure you've watched a good mix of pro & con videos of the Byrna devices? I'm assuming you are considering the handgun version. After seeing several videos I came away unimpressed w/it's ability to quickly neutralize a threat, but maybe just the deterrent effect of it looking like a gun to an aggressor would serve the purpose? Only you can decide that.
But when you see a guy hit twice in the chest & he says something to the effect of, "Is that it? Did the balls not break?" And then about 30 seconds later he starts to notice effects, it's just not inspiring. BUT...if a bad guy assumes its a real gun of some sort & breaks contact w/o it having to be fired, then it really was useful & effective, so maybe?