A lot of people feel that pepper spray is all made exactly the same, but this isn’t a fact. The hottest pepper spray will have the greatest concentration of capsaicin within it. This means that it will be made from good quality peppers, but also that it will have much more of an ability to burn anyone who has been sprayed.
Having the highest ability to burn somebody means that they will be more unlikely to just brush it away when they are hit with the spray. This offers you much more time to get away, potentially preserving your life.