I snapped a couple of spikes when I was tipping my EP500 forward so I could see the amp to make adjustments. My bad for assuming they were as tough as they looked -- although I suppose that's quite a bit of shearing force for any relatively narrow hunk of metal to deal with. They broke right at the point where the threaded part meets the cone. I was able to extract the remaining threaded parts using a pair or pliers. Now that I no longer have carpet in my living room, I don't really want the spikes anyway, so I lucked out.