I have had experience in the past that some thumb break holsters will disengage the thumb safety when the snap is closed. Not a real big concern when pistol is holstered since the strap is between the hammer and the firing pin but as soon as you unsnap it, you now have a pistol completely off safe since your usually holding the gun a this time and the grip safety is depressed. I would really look at this closely before I would opt for a thumb snap holster for use with a cocked and locked 1911.
Think about the reasons for the thumb break, and the reason for carrying cocked and locked. The two nearly defeat each other.
The thumb break is for security to hold the gun in the holster.....not really ready for quick deployment. Whereas, carrying cocked and locked facilitates a quick draw with the gun already cocked and locked only by the slide safety, ready for quick availability. I know of many that carry with the slide safety off as well, relying on the grip safety to prevent accidental discharge, not a condition I recommend.
Opinion... unless your carrying in a combat zone, or a LE in CQC, do you really need a cocked and locked condition for EDC to Walmart or to gas up the family car?
Myself, around home I carry a pocket 380 in case a wayward coyote would wander inside my given perimeter. When I leave home, first and foremost I avoid known danger areas, every town has them, I just go around. All my Rambo moves died when they stopped showing reruns. Otherwise, I carry one of my 1911's, chamber empty, hammer down, full magazine. So far, 69 years, and I'm still here, I either live a charmed life, or my plan is still working, and I've never had reason to shoot anyone since leaving the south pacific theater.
