I see many folks here debating the Hi Res or Non Hi Res displays on the 15" MBP. For those looking for the Hi Res option, few are interested in the 17". Is this purely a cost factor? It does not appear the 17" has that much larger a chassis and would not be all that more cumbersome to carry. Yet the display would be easier on the eyes a bit over the Hi-Res 15". I am wanting a new MBP (2007 15.4" 2.4 C2D here), but I am leaning to the 17". So I was just curious why so many pass on the 17" in favor of the 15"