Ken Shapiro,
I have always had spinners in preference to the hex nuts for two reasons.
First, the stupid little spanner in the tool kit is not up to the job and whilst hitting it with the provided hammer it always seems I am going to hit the wheel arch.
Second, once fitted and tightened, the spinners are self tightening and look the part but as always it's a very personal choice.
Why are spinners exclusively self tightening?
I believe he's referring to the anti rotation of the left hand and right hand spinners. The front hubs are RH and LH specific and while rotating down the road the spinners are "supposed" to stay tight on their own.
Years ago Chrysler cars all had LH and RH lug nuts. What a pain they were when you mixed them all up. They found that it was not that big of a deal and conformed to all the other US manufacturers and use only RH threaded lug nuts since.
