While they have some drawbacks spools are predictable and reliable. About the only time I don't like the spool in my street car is in parking lots. Some people on here act like a spool will kill you in the rain, its not bad, and its predictable. A locker is more likely to come around on you when it transitions from ratcheting to locked. My Jeep has had a locker in it for 15 or so years and it wants to kill you in the rain, you just have to know when its going to make its move lol.