I just did my rubber roof with this stuff.

Not cheap at HD, but I used it on my flat house roof a year ago and was pleased with the results, so just last week did my camper.
My camper 16 years old rubber roof did hold OK, but the years cost it few cuts and seems no caulk would stick to it and I tried at least 8 different, including marine stuff.
The Silicone coating looks great, giving it shiny, but soft finish.
It is partly self-leveling, so easy to apply on flat roof, but challenging on sloping surfaces.
MY front cap had some repairs on it and original labels washed out, so I am thinking about putting the coating on whole front cap as well.
Already did window rubber seal, who had some mildew stains that would not clean.