I have a number of 1911s. In fact, most of my pistol collection is 1911s, inlcuding the mini-variants in 9mm.380, and .32 ACP. Love 'em. But for me, a carry gun needs to be DA. I just don't shoot my 1911s enough for it to be second nature to me. The muscle memory isn't there. If my safety is at issue, I want a simple point-and-click interface.
I suggest you keep the LC9, and go buy that STI. Decide for yourself which one you are most confident carrying.
Just be aware that 1911s are like Doritos.
