The thing we must remember is that a thumb safety is not an automatic safety. It is not about safety when dropping the pistol. Its more about a brain fault in you or someone else, or a combatant firing your pistol more easily than without it (think shades of gray). I fear myself or someone else accidentally pulling a trigger on a chambered pistol, or having to wrestle or react to a combative that gets hold of your pistol - a thumb safety might give you that second or so to react. However, I fear not remembering to disengage the thumb safety when a second counts. A compromise between the two is to not chamber a round on a pistol without a thumb safety. But, that means if you need to ward off an attacker with your weak hand that you will have difficulty racking the slide to chamber a round, not to mention the time it takes to rack the slide, the noise it makes (in other circumstances), and the reduction of rounds ready to fire by one (most likely in other circumstances). On a pistol without a thumb safety in a holster with a finger release or other trick to release it gives one a little more safety-confidence if you choose to carry with a round chambered. Perhaps it is a question of tradeoffs and your personal taste and circumstances that will help you to decide to go with a thumb safety or not. For some purposes you may prefer to have one, for others not.