You guys are making me lean towards a spool for my street car. I ran a spool in all my cars over the years because they were also raced alot. The spools were ok but tend to be annoying when turning in a parking lot or if you are trying to push your car around in a driveway if the motor isn't done yet, it is almost impossible to push the car with the front wheels turned.
But, I have a Duster with a stroked big block and if I decide to drive it to one of our local dragstrips and make a few fun passes, I'd have zero confidence in my cone-type factory posi unit(8.75). A spool with some 3.23 gears and some drag radials might have to be the way to go.