The 220.55 magnet is rate for about the same, 1.18" so I don't think it would be much better and from experience, it will also fall on 1" if you get moving fast. The 220.56 will definitely do the job, it is rated for 1.57" but it is about twice the price of what you have and my experience from using a stronger magnet is they are much harder to move so you can't get too "vigorous" and that is probably the main reason they don't fall off, but it also scrubs harder so less passes are needed.