When you're craving designer frames and shades from cult names like Chrome Hearts and Loree Rodkin or style heavyweights like Tom Ford, follow the well-heeled tastemakers to this SoHo wonderland, the flagship of Luxottica, a Milan-based luxury eyewear brand; the performance and high-fashion specs are appealingly displayed on aubergine-tinged Mondrian-like shelves, and opticians are on hand to...