Hi Steve;
If they've been hard glazed, then you should be okay. You "may" suffer
scratches in the glaze, though - depends on how many of your friends wear
steel heels. Our kitchen tiles are of that type, and while a few are cracked
(they are at least twenty years old and were laid too close together), they
are otherwise exactly as when they were first laid.
If only I could say the same of myself...........
(With apologies for lowering the tone yet again
Tim