When evaluating quality, prioritize high-denier polyester or nylon (e.g., 900D to 1680D) for superior abrasion resistance. A critical feature for high-end markets is the Thermal Guard Compartment, which uses foil lining to protect racket strings from temperature fluctuations. Ensure the bag utilizes heavy-duty SBS or YKK zippers, as zipper failure is the most common quality complaint. For ergonomics, look for thickened EPE foam shoulder straps and a breathable mesh back panel to enhance user comfort during transport.