I've had my Simms boots for over a year and have yet to take a spill. Metal studs, that screw into the bottom of the boots were also bought but I haven't "felt" the need for them. If I waded on more large flat rocks I could see where the studs might be more safe. I bought the boots because it's just a matter of time before Missouri has it's first case of diddymo. I kayak fish a lot(with waders) and also stream wade. I could be in the Maramec one day and the Big Piney, Little Piney or Gasconade the next and conseration area lakes also and could transport a lot of plants or organisms that don't naturally occur from watershed to watershed. This was another big factor in my making the switch from felt to rubber soles with no regrets. I always make sure to sponge out any water that gets into the hull of the kayak. This is another point of entry for invasives. Our trout parks already have or will be initiating wader wash stations soon, hoping to encourage people to use them.