So I made Nano Speedy comparison pictures for you! The leather and canvas feel totally different.
Mono NS is quite stiff, the opening is a bit more thight and especially the handles are stiff when moving up and down. Leather NS is really smooshy soft, opening is wider and handles are moving up and down super smooth. Overall they are quite similar in size besides leather being a bit more "fat" but I think that has to do with the microfibre lining. Both bags are stuffed with the exact same air pocket on the pictures.
Talking about the inside, leather NS had the microfibre lining but I'm not perse a fan. The lining is only stitched to the sides of the bag so the middle part is moving around quite a bit and this also takes space from the inside. Mono NS is definitely roomier! And I think the pink lining will be prone to getting dirty.
The straps are equally long and have the same amount of holes. The leather strap is much more flexible and supple then the vachetta strap.
I think that's about it!

I don't have a favorite yet

what do you think? PS. I was in a room with very bad light and it's a sad and cloudy day today here hahaha, so colors look again different.
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