I have an Epson WF-4730 printer. I print 95% or more of the time using "black / grayscale" mode. I find that even so my color cartridges need to be replaced frequently, as in 6 to 8 weeks. I would have thought that by setting black/grayscale in the preferences that color inks would not be used at all. Apparently not so. Can anyone set me straight on this?\n\nFYI, this is a personal use printer. It is not a high volume business or home office unit. I would estimate that I go through about one ream of paper in a month.