In regards to pepper spray, I have been certified live hit with Sabre, First Defense .4, and Freeze. While they all sucked to get certified with, some more than others, they did not take away my function completely. At best, pepper spray is a distraction to get away, get to/employ another non lethal weapon, or go to a lethal force option. One should NEVER expect pepper spray to drop someone on the ground for 2 or 3 hours. It does not happen. With that in mind, I carry a can of Freeze (the worst of the sprays I have been trained in) in my pants pocket. Pepper spray is not the best option, just an option. As someone else has mentioned, pepper spray has no winners. Whether you are on the pointing or receiving end, you will get some. In order to reduce this (especially indoors) I recommend getting a gel based pepper spray.
In regards to HD firearms, a 380 in a pocket beats a 12ga anywhere you can't get to.