Cleaned and treated mine today following a recommendation from a friend that he uses on his ragtop.
Brushed the roof, used a lint roller to remove the rubbish and then applied a liberal coat of Fabsil. Available online or from any camping shop and about £24 for 5 litres. Brushed on with a paintbrush and the top absorbed about a litre of this stuff. Leave to dry.
It is fully waterproof and the liquid also has UV protection, hood looks like new and should have about six months protection. The water just beads and runs off. It is available in a spray can but this doesn't offer the UV protection because of the propellant used apparently.
Hood has come back to a deep black, not a mark on it & will see how long it lasts.
