I bought this 2011 E350 in really nice shape, paint is great but maybe not up to BITOG standards When I run my hand on the surface I can feel it has a very slight grit feel to it, not the buttery just-waxed feel. The car was waxed before I bought it but I don't know what brand. So I start a bit of internet looking and find that MB uses a ceramic-based clearcoat system that seems to be a bit tougher to polish out. My initial plan was to use a clay bar followed by wax but happy to defer to the experts here. What would you recommend for this daily driver, generally parked under cover at home and work? thanks.