The issue I'd like to talk about in connection to this thread, is why I've seen such rancor and disgust from much of the no-manual-safety crowd aimed at safeties and those that have them for the past twelve or so years? Why can't we just leave people be with their decisions?
Every now and them an article, video, podcast, or forum thread goes into how every single form of manual safety on a non-1911 defensive pistol (strange they stop there), from thumb safeties to grip safeties (but not trigger safeties, again, strange) will get you killed that one time you might (but probably won't ever) need to use it, and is often an indicator of naivety, lack of experience, or tactical sophistication.
Here's what I think after experiencing all different kinds of options... I think there's a group think attached to a sunken cost decision bias and maybe functional fixedness bias. When dealing with a polemic like yes or no to manual safeties, each has to make up their mind with their own applied logic and use cases. For some, once you decide, anyone else's personal logic seems to be an afront to your personal logic and reasons. Like I or WE NEED to know we got the best, and there is no other way in which MY or OUR choice isn't the right or preferrable way. This means that the very fact people live different lives or have differing opinions feels like an active attack against someone with little else to form an identity on.
There are arguments for and against... the arguments against are that they're another failure point if you need that thing to go bang, which is a one in a million chance for most (but not all) Americans. On top of that, what are the chances that it'll fail the one time you need it and not the thousands of times you are practicing with it at the range before to let you know there's a problem? What are the chances those failures aren't reported online through video reviews or forums like this? I've heard about grip safety/roll pin mechanical failures with old XDs, though I've never witnessed any myself. I've never heard of a failure of a thumb safety, which is an exceedingly simple control bar that I would argue possibly makes the trigger linkage stronger and less likely to take damage when not in use, though it most likely does alter the trigger weight and feel a bit negatively for most guns.
The next argument against is the training argument... you better be quick and smooth on the draw, which is kinda like, sure... but you should be like that firing the gun period. I CCW qualified with a manual safety 365 in CO as well as a manual safety Shield 45 in TX, both times from the holster, and one including a moving/approaching target at an indoor range, and I had the highest score in one class and like the third or fourth highest in with the small 45.
Does carrying a thumb safety gun make specific practice and muscle memory more important? yes. I can not draw a gun from a holster while target focused WITHOUT sweeping down with my thumb now. It's part of the draw regardless of the pistol. To me that issue is solved, train the same so that you can operate any pistol from a holster without thinking of it.
But I don't see people arguing that you should train for safeties, I see them saying that safeties on the gun are a bad idea, will get you killed. These are the same people that want you to search the inside of your holster like looking for gold a cave in case something is in there to defeat the trigger "safety" and blow your bits to... ah bits. Sure. That's great training advice, but don't say that an additional check on safety while conducting an inherently dangerous act is bad and you should rely on muscle memory and training instead, then say you can't rely on muscle memory and training to navigate an additional safety feature. What's the most likely statistical firearm danger... you ND because you're an idiot or an idiot makes you put him down in a Ol' West-style draw off because you didn't wait to get the drop on them or wait for your background to clear?
I carried Glocks, M11s, and M9s in the Army in reverse order, the last being striker-fired and the others DA/SA with sometimes tricky slide-mounted safeties the Army made you use. Since, I've carried M&P's, and Walthers, a Glock, Shadow Systems, and Sigs since, all stiker-fired, two without safeties, and M&P's and Sigs with thumb safeties.
I don't hate that Glocks and Walthers, and pretty much every striker gun out there doesn't have manual safeties, but for me, I can't figure out why there's a contingent out there determined to brow beat and shame thumb safeties out of industry adoption... especially with small guns that could find all kinds of weird use case scenarios, like being in office drawers ready to go, or a hiking chest rig, or around a calf or ankle, it makes sense to have a way of securing the trigger if the kydex won't fit the use.
I'll continue to carry what I will, sometimes favoring thumb safeties, as a small contingent of gun owners do because they're still being produced. To me, in many cases, the marginal everyday safety benefits far outrank the astronomically narrow and low defensive use risks. I'll work around the minor trigger debuffs, which to me is the strongest argument against it.
Sorry for the essay. I've been seeing affronts against safeties for over a decade and quietly rolling my eyes ever since. Got the demons out now. Carry well and carry on.