I use a couple of similar DeSantis off-the-rack leather OWB scabbards w/thumb break for my own M&P 40C and a SW999c (since I could buy them through S&W for an armorer's discount
). Not too bad, all things considered, for a factory cookie-cutter leather holster.
I prefer a Comp-Tac standard style paddle (FBI cant) for the M&P 40c, though, as well as for my full-size M&P 45.
I have other plastic (kydex, concealex, whatever, etc) paddles & belt slides which I've accumulated and used over the years, but the Comp-Tac is simply the best of any of them.
For leather, my favorite concealment off-duty/./plainclothes holster of all time has been the Hume H726. I've them for years for different models, although I haven't gotten around to ordering one for my M&P's. I have a number of them for different S&W 3rd gen pistols, and my old Colt Commander. They've changed over the years in some minor aspects ... belt slots vs. tunnel belt loops (they claim are stronger), and a plastic cap on the thumb snap (instead of adhesive felt covers, which I prefer, and replaced on my newer H726's).
http://www.donhume.com/index.php?main_page=product_info&cPath=65_5&products_id=49
The H&26 has a semi-open breakfront design with a low-cut opening that allows for a
fast presentation without the pistol having to be lifted as high as for a presentation from a typical pocket-type holster body. That being the case, it probably isn't going to be "legal" for some competitive venues (IDPA?), but I don't do gaming. I found it very fast, indeed, when having to draw while working plainclothes over the years. Might be easier for someone with shoulder issues, too, since the elbow doesn't have to be lifted as high for the draw stroke (the old 'elbow up/elbow down' technique).
Just some thoughts. I generally don't shill holsters.