Using ultrachrome ink cartriges, does the 2200 vs 7600 vs 9600 have the same or different costs per square foot of image printed? Which is the least expensive; which is the most expensive? I checked the Epson web page, but the capacities for the 7600/9600 are given in a different unit systems which I didn't understand. Do they all have the same ink delivery systems, or do they vary? If so, which is best, which is worst? Does it makes sense to purchase used, or should one stick with new printers?