I've found a rather unconventional use for these, studding dirt tires on an R1 sportbike. Yes, it's insanely dangerous, but far less so now thanks to iGrip studs! I really appreciated how easily these studs are installed, which is a major plus because I have nearly 400 per tire. They screw right in without any fuss thanks to the included drill bit/socket. They're similarly easy to remove and replace with the same tool.
I had some fleeting concerns that some studs might fly out during heavy use, but even at ridiculous tire speeds they're all still exactly where I put them.
How durable are they? Extremely. As an example, I broke traction on the rear tire to spin the bike around over ice in my driveway. The studs chewed through the ice, and then actually gouged--measurably--into the cement beneath it. Woops! I should have known though, tungsten carbide will chew into rock.
Overall very pleased with iGrip studs both for ease of use and functionality. I have yet to find and negatives!