I just got a preloved medium with the zippers. I find it harder to play Tetris with my things (can’t see inside and can’t move my hand inside a lot), so I feel like I am not able to maximize the space easily.
I don’t have a problem with my hand getting scratched by the zipper. It is not too sharp or blunt.
Despite the difficulty with getting stuff in and out, I like the fact that my things are more secure and the added leather will help keep the structure of the bag.
This guy does a good review on YouTube! Search medium lady dior zipper versus flap