SOUTH PLAINFIELD, N.J.--(BUSINESS WIRE)--Tumi Holdings, Inc. (NYSE:TUMI), the leading global brand of premium travel, business and lifestyle products and accessories, today announced its financial results for the first quarter ended March 29, 2015. Jerome Griffith, Chief Executive Officer and President, commented, “We met our bottom line objectives in the first quarter with strong gross margin improvement and disciplined cost controls. Sales grew 4.6% on a constant currency basis. We were up ag