I'm probably paranoid about the thumb safety on the Shield. I LIKE it. I have it engaged when holstered and any other time except when actually ready to fire the weapon. I have gotten used to having it and that it operates differently from the previous S&W I had which had a decocker type safety which went UP instead of DOWN.... Took me a while to get used to the change but now my brain seems to be in synch with reality....

I use a kydex holster most of the time IWB also since I have a "thing" about leather holsters that might get a little fold and press the trigger on a pistol with no thumb safety. I truly desire not to shoot myself in my own butt .... or anybody else for that matter ....

JMHO