Good point Barry. For large prints at normal viewing distances, the difference is likely not noticeable. It raises the age old question of "How good is good enough?".
Honestly, I think the difference in a 40x30 print would be noticeable. Viewing distance has really changed in this day and age and most people still think you should be able to walk right up to a print of any size and see great detail just like zooming in on the computer (I am talking non-photographers here since most photographers should understand that). Hang a 40x30 in your house and watch how many people walk right up to it to view it. This is why I limit the size of prints I sell to 40x30, the good lenses can pull it off for up close viewing.