On intact newer 149 and 146 models the ink window is basically well readable. Clouding can arise through long-term ink exposure; after flushing the window appears clear at first, but on refilling with ink the clouding becomes visible again. Certain inks (e.g. heavily pigmented) can contribute to deposits, which is why thorough cleaning is recommended. Anyone who does not need exact ink level can live with an approximate display; for precise readability holding against a light source helps.