From what I've read, the physical sizes of these two lens are different, 0 is smaller/lighter and 1 is bigger/heavier. Also the 0 has the fastest shutter speed of 1/500, 1 has fastest shutter speed for 1/400.

So is it safe to assume that Copal 0 is better? It's lighter and has faster shutter speed?

Will the copal size affect the image quality?