And the V is much faster, more water/dust resistant, and has memory storage, you can download shooting data to a spreadsheet on the computer so you don't have to log any shots, it will tell you your f stop and aperture, distance of focus(I think) and camera you were using, time of day if you want, etc I think it may do film speed too, it's basically like a digital in that respect, but takes film so you can focus on shooting and not feel the pressure to spend time recording everything on paper.
So that's some of the better functions of the 1V, oh and along with the 45 auto Focus points, it's metering matrix is extensive to give a better exposure based on light on the entree scene (advanced weighted metering) and much more I'm probably forgetting.
They both share the same power winder/motor drive, the 1V with motor drive will do 10 fps... Silly... But good for birding and sports (finish line) type photography.
Not sure what important things I'm forgetting but the 1V was a revolutionary product.