Hellos: I am considering buying a used 5D Mk I. I found a good one with low actuations and decent price. I have a 550D and started into dSLR last year. So, i don't know the history of 5DMkI. Do you consider the quality of this as good or close to the 5D Mk II? It has 12.8 MP so you know...with the pixel density, is there a difference in your eyes/experience compared to MkII? Off-course, i'm only concerned with stills. And i am also planning to go with a 5DMkIII when that comes out. Saw this deal and wondering if i should pass it up?