3M Caulk Remover will soften and loosen any silicone caulk. Follow up with a rag and a solvent or very strong butyl soap. Usually, I will apply the caulk remover and cover with plastic wrap to sit over-night. The next day, the remaining caulk can be removed with a rag or plastic tool.
Proflex RV or any of the other Geocel polymer sealants will take days to dry in typical ambient conditions. After drying, the polymer sealants are impervious to dirt and dust. Sikaflex, AFAIK, is a urethane sealant. It cures in the presence of water vapor. It dries much faster than the tripolymer sealants, has less flex, and less adhesion.