Every major automaker has convertibles, retractable hardtops, or high-end European cabriolets, but can any brand match Mini for its commitment to droptops? The convertible Mini Cooper, Cooper S, and John Cooper Works combined accounted for at least 12% of all sales in the US so far this year for the British brand. All weighing under 3,200 pounds, the Mini droptops are agile, fun, and reasonably quick. Time behind the wheel is most rewarding.