I've had Sigma computers for years, so I can't speak to the durability of the Cateye stuff. I've been caught in many downpours over the years with no ill effects. When I was in college the bike (and computer) lived on the balcony through two winters on the 3rd floor of our complex. Still worked every spring without a hitch. I would assume similar durability out of the Cateye stuff, but like I said, I've never owned one. Mine were also always wired computers. So that might have helped the durability of the sensors, and pickups.