I have never in all my years of sport shooting, training or instructing have I seen a hogue mono grip fail. Not that I am saying that it can't happen but it does come as surprise. I have had to shelve a M10 and move my grips to another M10.
I also looked after the M10's at the various ACC's that I worked for and never seen a breakdown. Even casuals that swore by them brought them into work and put them on their M10's each and every shift. Thats a lot of off/on over ten or so years and they never failed.
My experience says that a Hogue Monogrip is not only extremely durable but well liked in the industry and by police officers before they switched to semi's. I have no issues now or ever in putting Hogue on my firearms.