The 1" cube magnet is incredibly strong and is not recommended for the inexperienced.  I have had a part of my finger caught between two of these and I would have to say it was one of the most unpleasant experiences I have encountered.  Plus, it was very difficult to seperate them as it requires two free hands.  Please only purchase this magnet if you are familiar with the power of neodymium magnets and you have a specific purpose in mind.

They can be incredibly useful as they hold a large amount of weight, but must be handled with care.