Protect-All Rubber Roof cleaner and conditioner here. Used it on my last camper and it did a good job cleaning then keeping dirt off. Just be careful after using the conditioner, it's like Armor All and it can be slick for a bit.
I liked using the cleaner b/c it meant using very little water, and I didn't have to spray off the roof with a hose, just use a bucket and a mop. So no need to wash the entire coach at the same time.
2000 F250 7.3TD Lariat
2008 Crossroads Cruiser CF32BL
2006 Subaru Outback 2.5XT Limited
2000 Audi A4 1.8T
Triumphguy on rv.net