The Mulberry Agenda organiser is in Oak Darwin leather and the Gillio Medium and pocket Mia Caras are in Gold Epoca leather
I am not a fan of the new Vegetable Tanned Leather used by Mulberry, preferring the now-discontinued heavier, thicker and grainier Oak Darwin. I think it looks better, feels better and wears better. I stopped buying Mulberry new when they stopped using Darwin, preferring to buy pre-loved instead. Mulberry’s new leather is called NVT – Natural Vegetable Tanned and is lighter, thinner and smoother.
I can recognize genuine Darwin leather at about twenty paces, and to me the only planner leather that comes close is the Gillio Epoca. time is the only factor that will tell which wears the best but my vote is for Mulberry Darwin in this regard.
My Mulberry planner is in agenda size (this was the former Mulberry medium size and is now their largest size, as A5 has been discontinued), which is A6. The Mia Cara picture up top has both medium and pocket sized Gillio Mia Caras, but the pictures below feature the pocket size. The Mulberry is from 2007 (7 years old) and has been intensively used. The pocket Mia Cara is about 9 months and has been lightly used.
My personal take on it is that the Epoca leather feels better to the touch than the Darwin. It is softer and smooshier and is very tactile. The Mulberry Darwin not so much, but it wears so beautifully. I reckon that in about 15 years the Darwin will have worn better than the Epoca but that the Epoca will still be softer and the kind of leather you just want to cuddle.
Here, for your perusal, are photos of my Mulberry and Gillio planners. You can see how similar they are in some ways and how different in others.