Cars like this BMW 640i Convertible is easy to love. It will carry as many as an SUV while being more capable dynamically. It has beautiful proportions, and is powered by an ultra-smooth straight-six, an engine configuration synonymous with BMW. Keeping the paint equally silky is HydroGlide, a ceramic coating engineered in Japan that gathers surface water in large sheets before they glide off together, minimising water beading that can cause chemical etching and watermarks. Instead of hydrophobi