My disclaimer: I'm slow but steady.
Last night, it took me just over an hour to replace 40 spikes in my boots. The ones under the arch don't wear. Of course, there were a couple that didn't want to come out so that took a bit of work. I had to get up to let the dog out and in too. While intrigued with something on the news, I found I was twisting the wrong way on one spike. How long does it take you?