I carried a full size autoloader in plain clothes for a large portion of my career. I learned a holster is not the place to go cheap. My best experience has been with a Galco. Don't waste time and money on a nylon or "one-size-fits all" type, IMHO.
I have a Galco and it is a very good hoster. For low profile shoulder straps, I prefer the Kramer. My Galco sometimes prints under a suit coat and the Kramer will not.