Hi.
I have tried all the boaty type cleaners non did a good job. But found a cleaner that works a treat, It was a spray garden furnature cleaner from B&Q comes in a green bottle, half the price of boat cleaners to boot.
John
Anybody used "Truck wash" great for lorry side curtains and engine/bilge cleaning can be purchased in five litre containers from most car accessory shops. I use it on the hull of my boat when its particularily grubby, you virtually spray on and watch the grease and grime slide off, rinse and polish.
Rob
acetone soes indeed remove some marks. BUT it can leave others. It seems to depend on the exact type of mat'l. I d try diluted tincture of hlb's boat remover first.