Just curious as to what you carry with a manual safety that you think is OK to carry without using it?
this got me thinking (seldom a good sign, ), what about the early Colt/Browning guns that only had a grip safety?
And what about the new Remington 51? (is it in limbo?) didn't it also have just a grip safety?
For some reason, I'm slightly more comfortable with a no manual safety pistol that has a grip safety than I am with one that has the trigger tab safety.
And here, I'm talking about when trigger finger discipline is NOT involved.
Drop, or something snagging when your hand is not on the gun. (Hopefully never happens, BUT...)
If a branch, vine, wire, stick, etc., "pulls" the trigger, with a trigger tab type, only one unlikely event (pulling the tab first) has to happen. Force in a single direction only can do this, unlikely, though it is.
With a grip safety, not only does the trigger have to be "pulled" (or pushed) but force in the opposite direction has to act on the grip safety at the same time. This is 2 unlikely events (maybe 3 if you count at the same time), and that seems "safer" to me.
With every loaded firearm there is an element of risk. The gun's design sets a baseline, and how you handle, carry and use the gun is the major modifier.
To beat the dead horse one more time (OP's question) a manual safety is not a necessity to operate a firearm. A lot of people think it is a desirable thing, and a lot of people don't.
No matter if you are pro (manual) safety or no safety, there is some kind of gun out there in every caliber for you. Choose what YOU feel best fits your needs and wants, and enjoy!