A benchmark is the best in class for the products you are concerned with. Your customer may turn over a good competitive example for you to study in replete detail. The sample must be analyzed and measured in every possible way. Some features are subtle and hard to see unless you minutely examine it. This process can be described as cross-pollenization. In your case you may want to compare etched micrographs and hardness profiles from sections.
We have benchmarked competitive products as a team effort, and it is surprising how much detail can come out of this. We showed some experts from DuPont our typical products, and it was uncanny the improvements they pointed out. Sometimes we can benefit from a fresh perspective.