I don't know if anyone here has tried one of these Tuck This! holsters, but I had to try one.
I wanted to carry a larger framed pistol while wearing casual dress clothes at work. This seemed to be the answer.
Overall its a comfortable fit. It took me a while to get used to the setup, and of course access to your gun is limited, but at least its there. The side pocket seems to be setup for an additional magazine, flashlight, knife, etc. My belt was too thin though. The J-hook fits nicely over the top of my pants, but because of my belt being too thin the bottom of the hook would not catch on it. Also, if you adjust it I advise you to use some blue Loc-Tite on the bolt when retightening.
Here's what it looks like on their website: