In our severe climate putting leather under the front windscreen exposed to full sun is not a great idea.
Like any dashboard left in the sun if it’s not protected it will eventually suffer bigtime.
Mercedes along with other car manufacturers have been covering dashboards for years and seem to be getting away with it and if they weren’t they would have long since given up on it.
As an entry level covering they use Alcantara (polyester & polyurethane) for its suede look while being durable and stain resistance.
Nappa leather when used in higher end cars or as an optioned is soft and is sanded then coated or dyed to make it resistant against light and stains.
There are also non-leather materials used in some areas that simulate the look of leather.
I’ve have Nappa leather in my Mercs and BMW and they wear better than the pretend stuff in the Holdens but in saying that I also regularly treat them with conditioner and my cars don’t live in the sun.
The leather in my Beemer is as soft as and it has never shown any signs of wearing and it was our daily for a few years.
UV light is very high in Australia but it’s not the only hot country in the world and vehicles with these products are sold all over and they wouldn't be if they didn’t last.
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