First off, MIS is a very reputable company and they sell high quality dye and pigment inks. All of their carts have a full ink load.
The point I was trying to make is that you can buy another printer (any CIS compatible Epson) for the cost of a set of Lexmark carts or slightly more. Spend a bit more, get better speed and slightly better print quality. Keep the Lexmark but use the new printer with a continuous inking system for most of your printing. Based on your current $62 expense every two weeks, you'll save over a thousand dollars a year in ink costs, and with better print quality than the Lexmark. Even if you don't go with a CIS system, with another more common printer, you'll have access to much lower pricing for ink carts, in which the savings will pay for a new printer in a month or two.
As a photographer I do a lot of printing. I use CIS's with all my printers, and in three years I've saved about $6500 over what I would have paid for Epson ink carts. Not only that, but MIS ink is more consistent from batch to batch than the OEM inks, and the MIS pigments inks offer much better lightfastness.