Digital BW, The Print

Paul, I'm using color MIS pigs, and they have been in the printer for 
a couple of months now, about 1/3 used up so far.  The magenta line I 
speak of is on a border, pencil thin, but the image itself seem out 
of allignment, particularly noticeable when a figure is isolated 
againts the sky or a light area, the very edge of the figure is not 
straight and smooth, but slightly "pixilated" or UN Alligned"
As I said, this never happened with oem carts in the 1280, so I was 
wondering if others using pigmnets in the 1280 experienced this 
problem.  Is it inherent in the ink changeover, because the 1280 is 
made to use dyes not pigs???
Anyone with experience her, I would appreciate a comment.
As to Mis Allignment of my last post, I must have hit eneter or 
delete without knowing it and that was the foolish result.
Thanks
David