IWB certainly maximizes concealment. I just never liked the trade off in comfort, speed, and ease of reholstering. When I tried it I didn't like the gun pressed against my side, I felt like it was slower to draw without the gap created by being outside the waistband, and they collapse when you draw.
Admittedly I've never tried one like the one you linked. Does the leather maintain a decent opening under belt tension after the gun is out?