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A leather holster is typically thought to be better for a couple of reasons. First, it is molded to a specific gun for a tight and proper fit. Nylon holsters are usually generic and not made for any specific pistol. Leather is more durable. Nylon holsters tend to rip or fray after extended use. I highly recommend that you spend the extra money and get a leather holster. You may also want to look into Kydex type holsters. Some good leather holster companies are Galco, Bianchi, Kholsters, and many more. Some good Kydex brands are Blackhawk, Safariland and Bladetech.