Traditional automatic blood pressure monitoring cuffs sell for $40 to $50, combining gray fabric tubes with pneumatic pumps and battery-powered black and white displays. In each case, you wrap the cuff around your arm, press a button, then watch as your systolic, diastolic, and pulse rates are monitored though the use of air pressure. Withings’ design does the same thing, except with more style. It replaces the gray cuff with a more attractive…