Stone Coated Steel Roof Help

Hey guys I have a large upcoming project that I have to use a stone coated steel product on. The existing roof is Decra. It seems like the only options for products are Decra, Metro and Gerard with Decra leading the industry. From an installation, warranty and waterproofing standpoint who do you think makes the best product? Not concerned with price between them, looking for the best product for my customer. Thanks in advance.