First use was faster than a pumice stone and less chance of going too deep.
This works better and quicker than a pumice stone.  It worked quickly  with the default blue roller.  I did notice that the motor did slow down when too much pressure was applied.  I slight side to side length of the roller did seem to work well  The slow down can be compared to applying too much pressure on a power grinder.  Just take time when using the tool.
Rating: 5 stars