I paid £60 per sqm for these honed filled 457 x 305mm tiles from Mandarin Stone. My tiler says they have more chips and marks on them than they should do. Unfortunately it has become apparent that my tiler is rubbish so I'm not sure whether to trust his judgment. I've noticed some grey bits and some rust which from reading this forum I know are not good. The tiler's comments have got me worried that the tiles are below par. Could anyone offer their opinion?