Top-down motoring seems to be getting more and more popular these days, or at least this is what premium car manufacturers are expecting. BMW India has introduced its third convertible for India, the 330d. The 3-series convertible will join the Z4 (launched in 2009) and the new 6-series (March 2011) to round off their convertible range.The 330d convertible features a folding metal hardtop and