PC-60 has a max print resolution of 600 DPI
PC-600 has a max print resolution of 1200 DPI
This is not that big of an advantage as most images will print fine at 600 DPI and sometimes even better at 300 DPI, I print everything at 600 DPI on my PC-600. Also I have found the ribbon saver feature on the PC-600 to be much more cost efficent over the PC-60 in several situations, I did some actual comparisons printing a one color sign with just randomly placed text, on the PC-60 we could only get 9 prints per ribbon, on the PC-600 we would get 23 prints, big difference huh? Think of it this way, if you have a 20" x 20" print with nothing on it but a 1/4" border around the outside the PC-60 spools the ribbon all 20" on every pass just to print the 1/4" border even though there is nothing in the middle to be printed, the PC-600 does not do this, On the PC-600 If there is more than 1 3/4" space (if I recall correctly) between objects to be printed then the ribbon stops spooling.