I have the Whiteside reducer and the Musclechuck reducer and prefer the Whiteside reducer because it is easier to remove once it isn't needed. In my experience the Musclechuck reducer is so tight it takes a pair of pliers to remove it. Please don't misunderstand me, the Musclechuck reducer does the job but so does the Whiteside reducer. Not only that the Whiteside reducer is several times cheaper off of Amazon.
When something is advertised as being foolproof there is always a better class of fool that comes along to prove them wrong.