Does it make sense to upgrade to the 1.67 from the 1.33 Powerbook 17". Getting that speed bump, increased hard drive, scrolling pad, double video memory and faster superdrive. Will I see a considerable difference in speed. Id probably sell it when the G5 comes out, so the additional money it takes once I sell it for the G5 would probably be half as much as if I were selling the 1.33 then.