Last year I purchased a Prestige boot and when it arrived I noticed a defect along a seam and promptly sent a pic and told them I would not use it and wanted to return it. They sent me a replacement and I was told to keep the old one.
The output shaft boot is unique to RR and although a bit pricey at first glance, think about it this way.....value your time vs the cost of a shop at today's prices and you come out way ahead.