A vote for Mohair, in black.
Wipe clean, any "environmental (= bird poo)" marks come out with carpet stain remover.
After going out in the rain it dries a bit slowly, but looks fantastic once it has tried and lightly brushed.
But pale colours? Not sure, like a light coloured carpet I reckon you could treat it with Scotchguard.
Scotchguard Dark red could look fantastic! .
