I've driven mine In the rain once (years ago). Not fun. Realistically most of us need no more than 1 speed (and usually only for state laws). I ended up getting sold the "required" 2sp switch kit, and after looking at the factory diagram and testing diagrams . Realized the factory switch and dash wiring can stay. Their unit removes the outside low speed park resistor wiring with the same signals, so less wires. Nice parts though.