Roller supports, whether multiple rollers or a single roller, have the common problem of steering the lumber off at an angle unless the roller is exactly 90 degrees to the machine from which you a catching the board. This is not so much a problem with a planer, but if you are supporting a piece off a table saw, it can cause the board to pinch between the blade and fence and potentially kickback. Other than this common problem with rollers, this is a quality product and works well. I especially like the tapered support which allows minute height adjustment with the crank.