The Dico Nyalox Cup Brush was everything I expected it to be. We had some residue leftover from grout on tile and this helped take it right off without scouring the finish. The brush does wear in one direction and needs to be reversed periodically to ensure even wear. I found it takes light grout off by using it level and digs by tilting it at an angle and applying pressure. Two brushes were able to complete 500sqft, we had a lot of residue, haha. Great product!