You may find those tiles are difficult to enhance the colour. The black inserts will probably enhance but the enhancer may make little or no difference to the whites. To check this after cleaning wipe the tiles with a damp cloth if they darken with water then they will enhance with a penetrating or topical enhancer.
I recommend either Miracle 511 Seal & Enhance as a penetrating enhancer or Miracle Mira Matte as a topical enhancer alternatively you can use both if you want double protection
Kevin